I am planning on making copper sulphate crystals for my nieces, but because it is hazardous to touch (and if it gets wet), I was wondering what would be a good, clear, waterproof coating for them, something that can be made at home easily that is non-toxic.if you have any ideas, please let me know
How old are your nieces? Have you checked the MSDS? Why would you want to give your nieces (or anyone else) something that is hazardous? This is irresponsible. I do have some ideas of what might work, but I'm not going to say, because there is no guarantee that it'll work. Instead, why not grow crystals that are safer (ie. sodium chloride, magnesium sulfate, aluminum potassium sulfate, etc.) or go to a gem store and buy some quartz crystals?
Just coat your Copper sulfate Crystal with . . . . Clear Lacquer Spray -- or -- Clear Lacquer -- or -- Nail Coat . The last two are preferable since they can be manually applied . Just completely dry your crystal before coating . I do not recommend to shape your crystal ( which will generate dust ) , please use the crystal with its original shape ( either Single Crystal or Aggregate Crystal ) . However , I agree with other answers that you should give the coated crystal(s) in a transparent box ( or use other crystals ) . To put Copper sulfate in a necklace or anything that will come into contact with human body is not a good idea . Chemistry Note : The Copper sulfate Crystal is actually Copper sulfate pentahydrate ; CuSO4.5H2O
If your nieces are old enough and responsible enough, simply present them with the copper sulphate crystals in cotton wool or tissue paper in a little transparent box, like the ones used for selling strawberries. do NOT do this if you think they may handle them. I still have a scar on my hand where I splashed it with concentrated copper sulphate solution many decades ago. If, despite everything, they do end up handling the copper sulphate, they should wash their hands thoroughly afterwards in cold running water.
