Thread: Calcedony Prep
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Old 08-01-2017, 07:32 AM
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Pete VanderLaan Pete VanderLaan is offline
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I would certainly try the cinnibar. I'm not really familiar with it. Glass never needs more than technical grade and the only thing you have to watch out for in compounds is to note what's there in what quantity. I think the mercury would be in very minor amounts if it indeed did work.Everything's minor. I think the silver nitrate content in a proper reducing glass body is 9 grams in 21 pounds.

The calcedonia does work best in the presence of a small amount of red iron which is a nucleator. The chemistry of he goop is long strands of molecules that absorb and reflect with variation. The effect is best when the molecules are large and they do gradually get smaller so the effect decreases. It works best in a high potassium glass and none of the cullets have potassium to any degree. They want cheap glass and it's why I make my own. As noted, stirring it makes it worse as all the color effect mixes and turns gray. The heavy reduction from acetylene does help but there's nothing like a nice fresh pot. Eventually it will turn transparent amber. Doing the cobalt becomes a fine line between too much and too little. Copper in very minor amounts causes a red strike in the lehr.
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