Prestige OPTIMA Gypsum-Bonded Jewelry Casting Investment Powder for Resin Patterns, Waxes & Alloys – High Expansion, 30 lb

Works well been using it for years. Gold, silver, regular wax. High tech 3-D grows need some extra help. The H2O has Calcium Nitrate Tetrahydrate 76Grams per gallon, and the wax grows need to be dipped three times in React-Shun by Jett a Resin Casting Barrier. These work well

This investment handles resin burnouts extremely well. I've also dropped molds out of the furnace without them cracking. This is my go to investment for all silver, gold & base metal castings.

Idk what this is

Very hard to wash out of small castings, which is what we want to use it for. Still unsure if they sent the wrong product. Expressed concerns to supplier. They say, we send right stuff, you make operator error.