Rubies.
Precious stones are called gems.
any stone which is beautiful and rare can be considered precious. Although a stone does not have to be rare to be a precious stone, such as a diamond is by no means rare but is about the most valuable of the precious stones. Others are Rubies, Sapphires and Emeralds. Most other gemstones are semi-precious.
David Yurman rings use a whole bunch of different types of precious gems and stones. To learn more about their opinions it is recommended to call them.
A jeweler works with precious metals and stones.
Jewelers work with precious metals and stones.
Her ring has several semiprecious and precious stones. Semiprecious stones are not as valuable as precious stones.
A person who sells jewels is called a jeweler.
A person who studies precious stones is called a gemologist. Gemologists specialize in the identification, grading, and appraisal of gemstones. They often work in jewelry stores, laboratories, or as independent consultants, using their expertise to assess the quality and value of various stones.
typesof precious gem
The Unit To Measure Gems And Precious Stones Is Carat.
If you think to precious stones they are compounds.
Semi-precious stones are "des pierres semi-précieuses" in French.