Lots of minerals are used for jewelry, the most common are the birthstones (a basic internet search will provide a list) and diamonds, most are crystalline in structure. Many minerals of the minerals used though are the same but have a trace impurity which changes their color.
There are eight minerals that are used for the manufacturing of jewelry. They are: Corundum, Beryl, Diamond, Quartz, Olivine, Jade, Turquoise, and Plagioclase Feldspar.
One of the most popular minerals used in jewelry are the quartz based gems. Amethyst, citrine, rose quartz, agate, smokey quarts and even clear rock crystal are extensively used. Quartz is a very hard and durable mineral and comes in a wide variety of colors and patterns making it perfect for use in jewelry.
The most widely used mineral is the Diamond. Greatly in demand, it offers the best reflective surface when cut properly. Sapphire would be the second most frequently used mineral.