How to Identify Rubies and Gems

By Brenda Priddy
It, rubies, gemstones, home
ring with ruby image by Alexander Potapov from

Identifying gemstones and rubies is a challenging process. For complete accuracy, it is best to take the stones to a professional jeweler or gem identification expert to confirm the identity of the stones. Rubies are one of the easiest gems to identify at home, and they don't require a lot of equipment to identify. The color of the gems can also be a large identification factor. If you want to become more proficient at gem identification, consider the purchase of a diamond tester, which tests the heat signatures of gemstones for identification purposes.

Step 1

Polish the stones with the gem polishing cloth. This will help in the identification process by eliminating dirt and other contaminants.

Step 2

Look at the general color of the gem, which is the first indicator. Rubies are the red form of corundum. White and other colors of corundum are considered sapphires. Members of the beryl family include green emeralds, blue aquamarines, white heliodor and pink morganite. Diamonds are usually white, although they can also be yellow. Opal is usually white or black, although it can change color or have a multi-colored hue.

Step 3

Inspect each gem in a microscope magnified 10 times. Check the dispersion of the light by shining a penlight through the gem. If the light is strongly refracted in full color range, then it is likely a true gemstone. Artificial gems will not refract the light into different colors.

Step 4

Hold the gem up to your eye, almost as if you are putting in a contact lens. Do not touch the gem to your eye. Look at a light source through the gem. A rainbow effect should be visible. Look at the visible colors. If you can see green and yellow, then the stone is not a ruby and may be a garnet if it is red. Rubies will display the red and blue light dispersions. Garnets will show a green or yellow band between the red and blue lights.

Step 5

Check the florescence of the gem using a UV light. A genuine gemstone will emit a florescent glow under a UV light.

Step 6

Use a diamond tester to test the heat emissions of the gems. Each gem has its own unique heat signature that identifies it. Follow the table outlined in the diamond tester to determine the identity of gems. Diamonds have some of the greatest heat emissions of any gemstone.