Cabochon cut :
Means a polished dome shaped gemstone stone, without facet.
Carat :
The carat (ct) is a unit of mass equal to 2 g. Carat is used for measuring the weight of gemstones.
Quartz :
Quartz is a common mineral from the Silicate family. Colored Quartzes will be called Amethyst, Ametrine, Citrine, pink Quartz... The most famous white variety uses in jewelry is known as "rock crystal".