Opal is one of the two designated birthstones for the month of October (the other being tourmaline). Famed for their beautiful assortment of colors, opals are a popular gemstone choice for many who appreciate unique, colorful jewelry. Here are 10 facts that you may not have known about this month’s birthstone:
- There are several claims about the origin of the name “Opal.” One is that the name comes from the Sanskrit word “Upala,” which means “valuable stone.” Another claim is that the name came from the Greek word “Opallios,” which means to see a change of color.
- Opal is the designated gemstone for the 14th wedding anniversary.
- The gemstone is revered as a symbol of hope, fidelity and purity.
- Opal is formed from rain and usually contains 10% water. As water runs down through the earth, it collects silicon deposits and then seeps down into cracks in the rock. After most of the water evaporates, it forms a silica deposit that eventually turns into opal.
- The discovery of opals on Mars led scientists to believe that water may have been found on the planet for billions of years than previously thought.
- The play of color in an opal refers to the rainbow-like iridescence commonly found in the gem. The assortment of colors seen in opals can be attributed to millions of tiny silica spheres that refract light and turn it into the colorful spectrum noticeable in most opals. These spheres have to be just the right size and in the right position to create enough color for us to see.
- An opal’s play of color is just one of the factors that determine its value. The other two are brilliance and size.
- Opals can be classified into various categories including white opal, black opal, fire opal, boulder opal, and crystal opal. White opal is the most common while black opal tends to have the best play of color.
- Opal is the national gemstone for Australia. In fact, an estimated 95% of the world’s opals come from the “down under” continent.
- With a rating of 5.5 to 6.5 on the Mohs Scale of Hardness, opals require a bit more care than other harder gems to ensure they don’t chip or break.
View our current opal jewelry collection online here.