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Borneo Day 5: Tuesday, July 25, 2017

Country lane near school

The country road leading to SMAN 1 Mandastana.

On our second day at SMAN 1 Mandastana, I was faced with a bit of a challenge. During my presentation yesterday on my school (American Academy of Innovation) I showed slides of my students doing chemistry demonstrations, including the well-known flame test demo, where nichrome wires are dipping into solutions of potassium, lithium, sodium, calcium, barium, strontium, and copper salts, then heated in a Bunsen burner flame. These elements have fairly simple quantum structures (one or two electrons in an outer shell) and emit very definite colors. As the electrons are heated up, they absorb energy from the flame and jump to specific higher quantum levels. They then emit the same wavelengths of light as they fall back down to their ground states.

Doing flame test lab

Doing the flame test lab with chemistry students at SMAN 1 Mandastana near Banjarmasin in Southern Borneo.

The students asked, through Nazar, if they could do the same lab. My response was, “I don’t know – let’s look and see what you have and maybe we can.” I didn’t want to commit the chemistry teacher to do a lab, but she seemed willing, so we looked through her supply of chemicals after the class and found cupric sulfate, sodium chloride, potassium chloride, and barium sulfate. No lithium or strontium, which give off the best colors, but at least these four will work. Then we looked at her equipment. She has a lab assistant, and we unlocked the cabinets in her storage room. They have one nichrome wire, alcohol burners, and a good supply of beakers. So we could make this work.

So this morning I went to the chemistry classroom first thing, about 45 minutes before the students were to come in. The teacher got out the chemicals, and I discovered something interesting: none of the chemicals had been opened, not even the sodium chloride. The equipment also appeared to be unused – not brand new, as the storage cabinet had some dust on it, but sitting there for I don’t know how long. No stains on the beakers, and the alcohol burners had never been lit. We had to scrounge around to find a cigarette lighter. At least the container of alcohol for the burners appeared to have been used – about 1/3 of it was gone.

Flame test 2

David Black helping students with the flame test lab at SMAN 1 Mandastana near Banjarmasin in Southern Kalimantan.

Now I know this is not the norm throughout Indonesia, as I had seen the Assistant Principal at the elementary school we visited do the Priestley Experiment, the chemistry equipment at the SMAN 8 Jakarta school was well-used, and I found out later that other teachers saw science experiments being done at their host schools. So I don’t know why the equipment and chemicals have not been used here. The teacher certainly knows her stuff, as I saw from the class the previous day when the students were taking notes on mole fractions. And she is very willing to do this lab. So it seems to me that she either hasn’t had the training/professional development of how to conduct labs and use her equipment or she is unwilling to use up her supplies.

It also appears to me that the chemicals and supplies were part of a package provided by the central government, with a set list of materials. As chemistry classes go, she was fairly well supplied, but the chemicals were stored inside the fume hood as well as underneath, and the hood looked as if it might not function or be hooked up properly. The school is 20 years old and all the sinks in the chemistry lab were rusted out and nonfunctional, so that I had to get water for my solutions from a container on the counter. It was not possible for me to inquire further to see if this condition is general throughout Kalimantan Selatan or other provinces, but I guess that this might be a common problem in rural schools in Indonesia. After all, it is a common enough problem in the United States. Many teachers in both countries do not do the types of inquiry labs that students need to understand the practical side of chemistry.

David with chemistry teachers

David Black posing with the chemistry teachers (left) and English teachers (right) of SMAN 1 Mandastana. I really need to get my name tag straightened out . . .

Once I had the solutions made, I lit an alcohol lamp and saw that its flame was orange, not the blue I’m used to in Bunsen burners or with methanol. But with repeated dipping and heating, the colors were visible except for the barium, which is always the hardest one to see. We were able to find or make five wires, and divided the students into five groups. They traded off the four solutions. I told them what the five chemicals were and what colors to expect. I found that most of the elements are named the same in Bahasa Indonesia, except that the ones with Latin symbols are also pronounced with their Latin names. For example, sodium is called natrium in Indonesia and potassium is kalium. The only chemical I had to learn was copper, which is common enough that an Indonesian word exists for it: tembago. I labeled the solutions A, B, C, and D and told the students that they would have to observe the colors in the flame, then make their best guess as to which chemical each solution was. It took some doing and many dips. The copper kept contaminating the results for subsequent chemicals, but the potassium was good and the sodium simply made the orange flame oranger.

Flame test lab

Students in the chemistry class at SMAN 1 Mandastana conducting a flame test lab. I had to improvise for materials and chemicals, but the lab turned our fairly well. It was a true challenge in global education!

When we finished, I had the students shout out which solution they thought each was, and they got it right. I understood the names of the elements in Bahasa Indonesia by this time, so I didn’t need as much translation. Barium had to be guessed by a process of elimination. Given the challenges of the materials and the alcohol lamps, which simply didn’t get hot enough to really see the colors well, this lab turned out quite well. I will never forget this experience of teaching a science lab in a foreign language using scrounged materials.

As I observed the chemistry teacher the day before, and as I taught this class, I was struck by how impossible this would have been if this had been any subject except science. Yes, Nazar helped translate, but I was able to use Indonesian words for the elements and explain a few things where he didn’t know the words, since he is an English teacher and not a science teacher. Where Nazar couldn’t translate and I didn’t know how to explain, the chemistry teacher and her assistant were able to. Science is truly a universal language, but I have never put it to the test like this before. I was even able to do some explanation of quantum leaps and color emission, which the students seemed to understand. I don’t know if they have studied this before, but I saw comprehension on their faces despite some fumbling with the translations, more so than I usually see in American students’ faces.

Flame test

Looking for the blue flame of copper (tembago) sulfate.

Nazar said we could treat him to American food today, so we drove back to the city. We passed a large mosque at a roundabout that we had stopped at on Sunday in order to say prayers and use the restroom, but now there was a protest going on in front of the mosque in the traffic circle itself. The signs said this was a protest in favor of Palestinians in Israel. We didn’t stop, as we had been told not to get to close to protests as the mood of the crowd can turn ugly fast. This protest seemed pretty peaceful, with a few banners and people chanting but nothing else.

PE class with Nazar and Craig

Before the chemistry class, we went out with some of the students during their PE class to visit the junior high school next door and to see the area. Notice that the students are walking (and running) on a rough road surface in bare feet. The girls wear PE hijabs which seem very hot to me to wear in this heat.

We found a Kentucky Fried Chicken place near the Duta Mall in Banjarmasin. It was fairly standard KFC, except for the steamed rice they served. You can’t get away from that. But I think I’ve had about enough fried chicken for a while. I was running short of money, so we found a currency exchange place not far from the hotel and I exchanged the rest of my U.S. dollars (about $60) into rupiah, which was quite a pile.

Interesting name for a store

We passed this store on our way to the school, and I got a photo of it this morning. It is the old logo of my college alma mater, a strange thing to see in Borneo.

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Borneo Day 4: Monday, July 24, 2017

Taking notes in chemistry

The chemistry (kimia) class at SMAN 1 Mandastana near Banjarmasin, South Kalimantan.

Today we got to do what we came all this way for: to teach at a school in Borneo.

All schools in Indonesia start Mondays with an early morning flag ceremony, so we had to leave the hotel early to make it. After breakfast, Nazar picked us up in the lobby at 7:00. We drove across the Sangai Martapura and onto the road leading north out of the city that we had used the day before. We turned onto Jalan Ahmad Yani and headed toward the Barito River Bridge, but before getting that far we turned north onto a narrow country lane. This traveled straight through rice fields and past scattered houses to a wooden bridge across a canal, then turned west. I could see the school to our north, a blue building next to a grass field.

Country road

Jalan Achmed Yani, or the Trans Kalimantan Highway. We drove on this out of Banjarmasin to the northwest, then took a smaller country road to the school.

I recognized it from looking up their website and talking about it to my students. This is SMAN 1 Mandastana, the school where Nazar and his wife teach. We passed the school and immediately turned back north onto a somewhat worn cement road leading to the front entrance.

Ride paddie

The school is north of Banjarmasin about 15 km and is in the middle of rice fields. This is the view on the way to the school.

Nazar drove up to the entrance and we saw a sign hanging up welcoming Craig and I by name. We walked in through a breezeway into the school’s main office area and put our bags in the headmaster’s office (except my camera bag), then walked out into the main courtyard. The students and teachers were already assembled in ranks, waiting for our arrival. Our big moment had arrived!

SMAN 1 Mandastana from road

SMA Negeri 1 in Mandastana, near Banjarmasin. This is the school the Craig Hendrick and I taught at for a week in Borneo.

It is hard to express how I felt. I was being given the honors of a master teacher, an education ambassador who had traveled all this way from America to teach at this school. It was difficult for my mind to accept that I deserved this level of respect. Yes, I had come from America to teach here, but although I have multiple award plaques and certificates attesting that I am a master teacher, I have never really believed it in my heart. I know I have so many ways to improve as a teacher, even after 26 years of doing it. I’ve known so many teachers who were more deserving than me, who should be here instead of me.

Welcome sign

Our welcome sign at SMAN 1 Mandastana.

I wanted to shout out that they had the wrong guy, that the name on the banner must be some other David Black and not me. Yet here I was – half way around the world, about to attempt to teach in a place I’d never heard of before to a people I knew very little about. How very presumptuous of me. Yet buried under all that uncertainty was a part of me that knew I had finally arrived, that all my hard work at being an education professional and presenting at all those conferences was finally paying off. That I deserved all of this. I wanted to bask in the attention. I wanted to run away. I was thrilled to be there. I was scared to death.

Students in ranks

Students at SMAN 1 Mandastana standing at attention during their Monday morning flag ceremony.

I finally decided that even if I didn’t know whether or not I was a master teacher, it didn’t matter. All I had to worry about was that I should be a teacher, nothing more. If the students will let me, I can find the common ground that will allow me to be what I know how to be.

Craig with teachers

Craig Hendrick standing with the teachers at SMAN 1 Mandastana for the Monday morning flag ceremony.

We were asked to stand with the other teachers, who were wearing khaki uniforms. The students were in white shirts and blouses, white hijabs, and gray pants or dresses. They stood with their backs to the morning sun, but it was directly in our faces and already blazing hot. As the ceremony progressed, I stepped out of line a few times ostensibly to take photos but also to turn away from the sun for a few moments, as it was making my eyes water and I was beginning to sweat.

Raising the flag

Raising the Indonesian flag at the Monday morning flag ceremony of SMAN 1 Mandastana.

A squad of students marched in practiced formation to the flagpole and unfurled the red and white Indonesian flag. A group of girls sang the national anthem, and the squad attached the flag and slowly raised it until it reached the top as the anthem ended. A teacher recited the five Pancasila principles from a microphone on a podium while the students repeated. Then we were introduced and each made a few remarks while Nazar translated. The ceremony ended and we took some photos of us with the entire school.

Craig and David with students

David Black and Craig Hendrick posing with the students of SMAN 1 Mandastana after the Monday morning flag ceremony.

As the students moved to their first period classes, we went into the headmaster’s office for a few minutes. He offered us some snacks and we answered his questions through Nazar. We were then ready to meet the students.

David with headmaster

Meeting the Headmaster (Principal) of SMAN 1 Mandastana.

There are two English teachers at this school. I went with Nazar and Craig went with the other teacher, whose English is also fairly good. The school is built in an almost enclosed letter C shape around a central courtyard, with the offices at the bottom of the C, the computer and language lab on the small right leg with the kanteen or cafeteria at the end and a separate wing almost completing the open part of the C. A new classroom was being built at the far end. On the left side, the longest side of the C, is classrooms with a tile walkway in front and a wooden walkway beyond along the inside edge. The front area of the courtyard is cemented and used for the flag ceremonies and for volleyball, basketball, and soccer. There is a small grassy area behind that, along with a greenhouse that is being built for the biology classes. The grass becomes more swampy as it goes further back, along the top curve of the C. The entire school is built up on stilts to prevent it sinking.

English class

Nazar’s English class at SMAN 1 Mandastana. This is the class that I first presented to, showing a slide show about my home, school, and family.

I walked with Nazar on the left side of the horseshoe. Racks of plants and flowers are growing across the tile walkway, causing us to step down onto the wooden walkway next to the swampy area. I wheeled my blue suitcase around these obstacles as best I could, until we could step up onto the tiles walkway for the top section of the C, where Nazar’s first class is located.

David with English class

Posing with the English class after our lesson. They like to take photos and selfies. They will pose seriously, then do a “freestyle” pose such as this one.

Since Indonesian students stay put in one classroom (except for PE or for classes that require specialized labs, such as Kimia or Fisika), the teachers are the ones to travel. Nazar’s morning English class was in the north wing. The students were excited to see me as I wheeled my stuff in and set up my computer. Nazar had grabbed a portable projector, as the one mounted on the ceiling in the room didn’t seem to be working. I had remembered to bring the power converter with me, so I was able to plug my computer into an extension power strip. I had remembered to bring a VGA cord and my conversion dongle, knowing that HDMI probably wouldn’t be available (but I had an HDMI cord, too, just in case – this is why my carry ons are so heavy). Fortunately everything worked, and I was able to project onto a light blue wall at the front of the class.

David iwith chemistry class

Posing with the girls in one of the chemistry classes at SMAN 1 Mandastana.

I had prepared two slide shows, one the night before about American Academy of Innovation and a second show with harder English about the trip my family made to the Four Corners region of Utah, Colorado, New Mexico, and Arizona at the end of June. This one was more about geography and geology.

David with chemistry boys

Posing with the boys in the chemistry class. They wanted a separate photo from the girls. There were more girls than boys in the class. I don’t know if this is the case for all science classes or not.

I showed the first slide show during the first block of the period (45 minutes). Nazar translated for me. The students watched carefully, and exclaimed when they saw the photo of my school on a snowy day. They have never seen snow in their lives. After, I asked if they had questions but they were reluctant to speak, probably because they were afraid their English wasn’t good enough. A couple of students were able to ask a few questions.

When the bell rang, it sounded exactly like the tones played in the Hunger Games movies to announce that a contestant had died. Craig and I both found this a bit unnerving.

Going to class

The inner courtyard of SMAN 1 Mandastana. Since there isn’t snow or cold weather, there are not internal hallways, similar to schools in California. The students wear gray pants/skirts and white shirts/blouses with hajibs and/or hats on Mondays.

During the second block of the 90-minute class, I showed my higher-level slide show on the geography and geology of the western U.S. They were interested in the comparison slide I had made between Borneo and Utah and the other four corner states, that Borneo is 3.38 times larger than Utah and just barely smaller than all four states. But as I showed the various national parks (Taman Nasional) and our route, I could tell that the English was too hard for them. They had fewer questions than I had hoped. I picked things up by opening up my blue case and handing out flyers, brochures, and other materials I had been given at the Utah Valley Visitors Bureau the day before I left Utah. They were excited to get them and have something to practice on.

Happy birthday

A birthday cake for a student in the Language Lab room.

At the end of the class, all the students came up and insisted on taking group and individual photos, including many selfies. They wanted photos in normal pose and what they call “freestyle” which is to pose in a less formal fashion. As I was leaving the classroom, all the students came up and did something they had told us about, but which still came as a surprise. Each student took my hand and placed it against their forehead or cheek or kissed it. This is a normal sign of respect for teachers in Indonesia.

Craig with class

Craig Hendrick teaching in the Language Lab room to students at SMAN 1 Mandastana in Borneo.

The bell rang again (another dead contestant!) and Craig and I traded classrooms. The other English teacher was teaching in the chemistry classroom and we waited a few minutes while the chemistry teacher finished up her lesson. This was the second week of school, and she was reviewing mole fractions (mol fraksi), a subject I don’t often teach until deep into second semester. Even though she was speaking and writing in Indonesian, I was able to follow most of what she was doing as the language of science is fairly universal. Indonesians use Arabic numerals just as we do, and with many words transliterated from Latin in a phonetic alphabet, I was able to follow much of what was written. The teacher was lecturing and writing on the board while students took notes. I walked around and noticed that the students’ handwriting was extremely neat, better than any writing I’ve seen in America (including my own).

Mole fraction notes

Student notes on mole fractions (mol fractsi). Notice the neat handwriting.

Once the lesson was over, I set up the projector again and went through my slide shows. When I came to showing some of the activities my students have done, I had a slide showing two students doing a version of the flame test lab as a demonstration, a lab I’ve done many times. One of the students asked if they could do the lab (through the English teacher) and I looked at the chemistry teacher, who was still in the room, and said we’d have to see what materials she had.

Library

The library at SMAN 1 Mandastana.

After the second slide show was done, I handed out more tourism brochures to these students. We took group photos and selfies again, and as they were leaving to go to mosque, they bowed their heads and kissed my hand as had the other class. This gets to the heart of my basic doubts about myself – that I don’t deserve the great respect they are showing me. Certainly I’ve never seen anything like it before. I wanted to bow back to them, but was told by Nazar later that I don’t have to do that.

Periodic table in Indonesian

Indonesian periodic table. Most of the element names are based on the Latin root words, such as Kalium for potassium (K). Some of the elements, such as Tembago for Copper, must be Indonesian words that predate the introduction of western science.

After the class was over and the students left, we looked through the chemistry supplies and discovered enough materials to make the flame test work. We’ll try the lab tomorrow. While looking through the classroom, I took photos of the periodic table hanging up at the back of the room. I could recognize most of the elemental names, based on the original Latin names, such as kalium for potassium and natrium for sodium. Only a few elements, such as tembago (copper) or beso (iron), were unfamiliar. These must be names that predate chemistry as a science in Indonesia.

Banjar houses craft

Student crafts, including a traditional Bajarese house, on display in the library.

As I walked back to the teachers lounge, I thought of how things had gone and my impressions of it. All of my teaching career I’ve wanted to make a difference in the world, which I have done. There is a part of me that would like to be well known if not famous, perhaps even remembered by history. Whether or not this ever happens, I can at least say that for this week, I was shown the greatest respect I’ve ever known as a teacher.

Teachers room

Teachers’ Preparation Room at SMAN 1 Mandastana. Overall, this school had a lot more light and seemed more airy than schools in Jakarta. There was no air conditioning, so ceiling fans and open windows were the only ventilation. Teachers wear khaki uniforms on Mondays.

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woad-stained-pict-warriors-john-white-bm

Pict warriors painted blue with woad pigment. With their blue skin and red hair and mustaches, these warriors must have intimidated even the Romans.

While we were researching dyes for our dyeing lab, I came upon the history of woad, a plant that produces a blue dye used by Europeans for millennia before indigo was imported. It originated somewhere in the steppes north of Asia Minor and was grown, traded, and transplanted all across Europe until it reached Germany, France, and England. During the time of the Romans, warriors from one tribe of Britons would dye or tattoo themselves with woad in elaborate patterns to frighten their enemies. The Romans called them Picts because of the pictures they drew on themselves.

woadballs

Balls of woad. In England, woad leaves were crushed and rolled into balls, then allowed to ferment to precipitate the blue indigotin dye.

During the Renaissance, woad trading and dyeing made whole towns wealthy. In England, many acres were planted to woad. The leaves were harvested and mashed, then rolled into balls and allowed to ferment in a shed. The fermentation allowed the indigotin dye molecule to precipitate out of the plant leaves. The process smelled rather awful, and laws were passed banning any woad dyeworks within two miles of a town.

woad_mill_1752

An illustration of a woad mill in France. The leaves were gathered, crushed mechanically, formed into balls, and allowed to ferment. It was a smelly process, done in the country away from cities.

The other major source of blue dye before synthetics were invented was the indigo plant, which is native to warm and humid climates. Different cultures worldwide have invented their own methods of extracting the indigotin dye from the plants. Japanese dyers would allow the indigo leaves to ferment in a vat to remove oxygen. In India, the leaves were also soaked in vats then treaded by humans to mash the indigo and release the pigment, which was dried and pressed into cakes. Once indigo became known in Europe, it replaced woad as the choice for blue dye because the indigo plant has more indigotin and is therefore cheaper to produce. One wealthy indigo trader, Heinrich Schliemann, used his wealth to explore the ancient site of Troy. Another, Percival Lowell, used his family’s indigo wealth to build the Lowell Observatory in Flagstaff, Arizona to look for life on Mars. Levi Strauss used indigo to dye his original blue denim pants. As you can see, it’s had an impact on history.

woad-shades-031

Young woad plants, with yarn dyed using the extracted indigotin pigment.

As part of my research, I discovered something completely unexpected: dyers had imported woad to Utah in the early 1900s and tried to grow it here. Since it originated in a high desert environment, it did well in Utah’s climate. In fact, it did too well. It got away from the dyer’s fields and went wild, growing all over the western United States. It is now considered to be a Class 3 Invasive Weed, which means it is almost out of control. The only way to prevent it from spreading further is to pull up the plants before they go to seed.

woad-plant-2

A woad plant, growing in the southwest corner of Salt Lake Valley in Utah. Dyers brought woad to Utah in the early 1900s and it got away from them.

I memorized the characteristics of woad plants, knowing I would want to try to find some and take my students on a “Woad Twip.” Woad has dark green leaves with a white vein. These leaves are clustered at the base of the plant. It sends up tall flower spikes with yellow flower clusters in the late spring. By fall, the flowers become brownish-red pendular seed pods with many small black seeds.

woad-plant-3

More woad growing in Salt Lake Valley. I discovered this by accident while collecting late rabbitbrush blossoms. The seed pods can contain hundreds of thousands of seeds in a single clump of plants, and can spread quickly.

By mid October the rabbitbrush blossoms were beginning to fade. I needed to collect as much as I could for continued experiments, so I found a spot in the middle of Mountain View Corridor in southwestern Salt Lake Valley where the rabbitbrush blossoms were still bright, and I stopped there after school on a Friday. While I was out collecting the rabbitbrush blossoms, I noticed a plant I hadn’t seen before. It was woad! So I collected several bags full of leaves and some seed pods, with the idea of trying to grow some in my back yard.

woad-leaves

Cutting woad leaves to extract the indigotin dye.

My chemistry students cut the leaves into pieces and also separated out the seeds. We looked up the ancient process of woad extraction and found some websites that describe how it is still being done at small farms in England. The process involves quite a bit of chemistry. I am attaching a PDF file that describes the steps. Here it is:

woad-dyeing-process-s

whipping-woad

Whipping woad solution to add oxygen and precipitate the indigotin.

In summary, the indigotin dye in woad and indigo is a rather delicate molecule. Too much heat will destroy it, but some heat is needed to extract it from the leaves. The chopped leaves are steeped in water at 90° C for 10-15 minutes. The leaf fragments are strained out and the liquid has soda ash added to make the solution basic. To precipatate the indigotin, the solution must be whipped with an electric mixer for 15-20 minutes to add oxygen to the solution. The solution is poured into dishes and allowed to settle. The supernate is carefully poured or filtered off and the final pigment allowed to dry.

woad-settling-dishes

After adding soda ash and whipping the woad solution, we poured into dishes to allow the pigment to settle out. We then poured off the supernate.

We took it this far in chemistry class. Our next step will be to put the purified indigotin in a 50-60° bath and add some sodium hydrosulfite to the solution. This is a reducing agent that converts the blue indigotin into leuco (white) indigotin, which will dissolve in water and turn yellow-green. It takes about an hour of careful heating without stirring to do the conversion. While it is simmering (but not boiling), the fabric or yarn must be heated up in a bath with some soda ash. Once the solution turns yellow-green, the hot fabric or yarn can be carefully added without dripping or splashing. After about ten minutes, the dye has absorbed into the fabric but not yet bonded. When it is removed and exposed to the air, the fabric will turn from green to blue as the indigo converts from leuco back to blue indigo. As it precipitates out, it bonds with the fabric. Hopefully.

woad-pigment-settling

Woad dye pigment settling out on the bottom of our dishes. We poured off the supernate and dried out the final pigment.

I purchased some pure indigo from Dharma Trading Company and was in the middle of heating the dye bath with sodium hydrosulfite after school on Tuesday when our fire alarm went off – an exterior pipe in our fire suppression system had frozen and burst, so we had to evacuate the building. I quickly unplugged everything and left. It was the last day before Winter Break. I hope to return by tomorrow and continue the experiment. If it works with pure indigo, I will demonstrate the process in chemistry with our own woad pigment when we return from break. I’ll update this blog post then.

natural-dyes-andes

Andean people with naturally dyed alpaca yarn and clothing. The purples and reds come from cochineal, the oranges and yellows from tree bark, etc. All cultures have solved the problem of how to dye cloth; dyestuffs are found around the world.

All cultures around the world have found ways to solve the problem of how to dye fabrics. They’ve found dyestuffs in plants, minerals, and animals; through continual experimentation they’ve realized that certain salts (mordants) will help make the dyes colorfast. The process of oxidizing, then reducing indigo must have taken a long time to discover. It amazes me that such a complicated process could be developed in many countries and cultures, each with their own way of accomplishing the same thing, and all to get a permanent blue dye.

 

nilda-and-acopia-women

Alpaca wool yarn dyed with cochineal.

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