Explaining the science of glassfrom @annakahoelkstudio

Transcript

Have you ever thought about how glass is colored because it's pretty magical? I'm not an expert by any means, but as I've been exploring making glassware, I've learned a bit more rank it's just such a cool topic. Much like ceramic glazes, which are technically also glass, glass is colored using a range of metal oxides like cobalt for blue, chromium for green, or manganese for purple. But historically, there are some really cool ones, like how gold creates a rich ruby red. The magic is that gold obviously isn't red. It actually comes out in expected yellowish clear color at first and only becomes red after being reheated to a very precise temperature in a secondary firing. All this from the raw ingredient being literal gold to the labor of having to reheat it has historically made red glass the most expensive and sought after color, and it's still relatively more expensive today. In tier complete opposite vein, a traditionally red pigment, iron oxide, makes glass that classic bottle green or brown when combined with sulfur and carbon. And because iron oxide is comparatively abundant and cheap, these are the colors we're used to seeing when we need something dark and UV resistant to protect perishables like olive oil and beer and wine. And it goes even deeper because small impurities of that same iron oxide are why clear glass is known to have that slightly greenish hue. And when you want something really untinted, you have to get low iron glass or sometimes they cancel out that green color with a slight amount of pink pigment complimentary colors. I just think it's cool that each color seems to have its own alchemy and the different processes and prices of these minerals is why we see some colors way more than others.