Autochrome: It's potato starch.

This is as large as it gets for you - I'm sorry.

I want you to know I've made a promise to myself that I would post at least twenty consecutive posts of good quality material daily, and have committed to a post daily for ever, but weekends are especially busy for me, dear reader, so we're going to keep the content on this one to a minimum since I have to hit the sack. This is an autochrome, it was the first popular use of colour in photography, existed only between 1907 and 1939, and was incredibly finicky and difficult to do. This autochrome does not belong to the Archive, it sped through it last September, but is the only one I have that has been scanned properly (I hope to change that soon). I think they are the gems of photography. They're lovely to handle, hold up to the sun and illuminate, and examine magnified.