Birthstone Colors and Months
Birthstones have a variety of different uses besides symbolizing the month you were born. Some of the more practical things are industrial equipment such as saws, grinders, cutting tools, and even replacing silica sand which is used in traditional sand blasting. Many precious gemstones such as diamonds are being used as drill bits and saw blades. This is because diamonds are the hardest material in the world and are virtually indestructible. The Garnet which is known for its abrasiveness is being ground up and used in sand blasting, as well as cutting through steal objects when mixed with high speed and water.
Look at a wonderful collection of engagement rings with a variety of birthstones as a main feature of their design.
Since birthstones are natural from the earth and form in vastly different environments, the same gem can be the same color as another gem of a different month. This allows people who aren't happy with their traditional birthstone color to switch to a different color but still keeping their original birthstone. This is commonly done with gems that switch to blue or baby blue from a different color.