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Domeroni t1_it6e3cq wrote

Reply to comment by hazelquarrier_couch in Researchers look to unravel story of Islamic glass found in Scottish castle - HeritageDaily - Archaeology News by GullyShotta

You're correct for relatively short timescales but medieval Islamic glass was mostly of the soda-lime-silica type. On the shelf of a medieval castle it'd last a few lifetimes. But in wet and acidic conditions we find that the soda and lime components of the glass on the outer layers would react and change the structure of the material.

Glass has an impure and uneven lattice (which is good because it allows us to mould it at high temperatures), meaning water molecules can seep into gaps in the lattice and draw away structural components such as the lime. This happens incredibly slowly since the structural bonds are really strong. But over the course of centuries sitting in a peat bog we see that lime reacting away, leaving a brittle and opaque product.

The process is called weathering and I'd really recommend the book "Ancient Glass" by Julian Henderson if you're interested and want to read more

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johnmuirsghost t1_it6jfzn wrote

I'm not interested enough in glass to read that book, but by God, I'm glad you were.

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totallynotliamneeson t1_it765le wrote

That's a the awesome part about archaeology. There is always someone who knows way too much about a material or item used in the past. It's also why my wife never asks me about stone tools but thats whatever haha

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nivison1 t1_it7hgxl wrote

I want to know about stone tools.

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totallynotliamneeson t1_it7ihkg wrote

May I interest you in way too much info about projectile points?

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Grwwwvy t1_it7hl6v wrote

Do you ever feel like stone tools fell out of fashion too early? It seems to me that most cooking and eating tools could be stone instead of plastic or metal. After throwing out a lot of teflon pans and easily broken plastic cups, it makes me think such things.

Are there any stone tools you think should be picked back up? I use a mortar and pestle instead of a food processor for instance.

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totallynotliamneeson t1_it7jcdi wrote

Eh maybe. There is a reason they were replaced in the manner that they were in many cultures. For example, along the Great Lakes we see that many cultures begin to replace stone points and knives with copper elements scrapped from copper trade goods as soon as they had access to the trade goods. Copper was easier to work with, easier to rework, and simply just sturdier than a stone tool. Once the British and French started trading copper pots we suddenly see that everyone is obtaining these pots and dismantling them to use the copper for tools. Parts of the rim would become knives or fishing hooks, for example. I'm generalizing for a bit, but the biggest reason people went away from stone tools is that they can be finicky to work with. I flintknap in my free time, and it can be VERY frustrating to spend an hour on a point only to have it break because I hit in incorrectly when trying to break a flake off.

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The_wolf2014 t1_it8yu2y wrote

There's a reason we still use ceramics for plates, cups, bowls etc... not strictly stoneware but I suppose it could still come under that bracket. Weve made items from ceramic for a long time and it's incredibly durable, cheap, easy to clean and tough. Look at how we'll preserved many roman mosaics are as well

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Larsus-Maximus t1_it9l5mg wrote

Of course, ceramics is just stoneware without most of the downsides

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Domeroni t1_it8g7pe wrote

Absolutely and same here lol. It's not just the material you study though - you learn loads about the people who used them, the place they lived in, the society they were part of and how they interacted with the wider world.

Also you learn so fucking much about their trash

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totallynotliamneeson t1_it8nub6 wrote

Oh look, another storage pit full of pot sherds and random faunal remains. Maybe a rodent burrow or twenty

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atkulp t1_it8udq6 wrote

Hmmm... Sounds like something Liam Neeson would say!

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Frenchorican t1_it96rcw wrote

Yep, I haven’t studied it in a while but I did an entire research project on 18th-20th century iron nails. I’m obsessed for no good reason, but I’m fine with that oddly enough lol

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totallynotliamneeson t1_it9bkrg wrote

The square headed kind?

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Frenchorican t1_itd9mf9 wrote

Mostly yes was working at a French Fort in Alabama where we found a whole bunch of construction materials and I found a whole bunch in situ next to a limestone foundation. Was super cool

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Gates9 t1_it81ysc wrote

This is a perfect comment and the reason I come to this website

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SaGlamBear t1_it8dw8g wrote

It always amazes me the rabbit holes of information you can go down into. I’m not sure I’m interested enough in glass to read the book ancient glass but I would absolutely watch a video on it.

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sotpmoke t1_it9e2ep wrote

Its impure and cloudy because casting was done at lower temps. Technology wasn’t that good yet unless you had enough money to get the fire hot enough.

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