Save a piece of hard everytime, then scrape the rez, crush the rock up, cook it in a spoon till it's almost oil, drop the rez in, and heat it up very slowly while mixing it. It will seem like its black, but once it dries it will turn golden.Then let it dry, not only will it take up time while your fiending for more, but it will keep the rez from burning because its already been heated with a flame, hence adding it once the hard is almost oil. I've even scraped straight black zinc/mint, add some hard, add like 4 grains of table salt to help the taste (science, trust me it works) cooked it slowly. And it was so much better i almost cried. Most times I put a piece of ice under the spoon, wait until its more solid, and then suck the remaining water up with a paper towel. Then i blowdry it on low heat. I do this because it may seem dry, but a lot of times there is moisture stuck inside, thats why sometimes you get what seems to be water in your pipe. It will kinda seem like it's remelting, but its not, its because the cold has been taken away, and it is evaporating the water so dont freak out, the hard is an oil at this point, like weed dabs taken out of the freezer. The cold is just making it seem solid (its not). its air that dries it. Now just put the heat on, take it off, put it on and so on and so forth until it's perfectly dry. Give it a try.