OPAL | TOURMALINE
Opal has a Moh’s hardness of 5.5 - 6.5. It is divided into three subgroups: precious opals, fire opals, and common opals.
Precious opals display rainbow-like hues that change depending on the angle they are viewed. Fire opal is yellow-red and is usually milky or cloudy. Common opals are usually opaque and show no play-of-color.
All opals consist of 3-30% water so opal is sensitive to heat. It is also sensitive to pressure and acidic substances.
High heat can cause color change and sudden temperature change can cause fracturing.
Use warm soapy water and rinse and dry to clean.
The name “tourmaline” comes from the Singhalese word, “toramelli,” which means mixed gems, demonstrating that it has historically been easily confused with other gemstones.
Tourmaline comes in a wide range of colors including pink, red, yellow, brown, green, blue, violet, black, colorless and multicolored. It can be both opaque and transparent and has a Moh’s hardness 7-7.5.