Depending on the gemstone and color each one has an amazing property that is not just their natural beauty but their healing and protective energies that has made them popular. In Feng Shui they are used to harmonize spaces as well as balancing.
Henna Art Candles - Tutorial not included in article. I would take any candle of choice, scented/non scented, either use delicate paint brush or a henna paste tube (looks like a mini cake icing tube), and decorate. Just stick the gems on with henna.