Carat :
The carat (ct) is a unit of mass equal to 2 g. Carat is used for measuring the weight of gemstones.
Tourmaline :
Tourmaline is a group of ssemi-precious silicates. Crystals may be green at one end and pink at the other, or green on the outside and pink inside, therefore called "watermelon" Tourmaline. Tourmalines come from Sri Lanka.