Nice and informative video! My exposure to glass has mostly been working with someone doing glass blowing and hot glass work, so even the clean cullet from the

Nice and informative video! My exposure to glass has mostly been working with someone doing glass blowing and hot glass work, so even the clean cullet from the recycling process would likely not be good enough there - it needs basically zero contaminants, because just one or two little dark spots in the clear part of a paperweight can be a problem.