Birthstone

October

Origin

Opal is the national gemstone of Australia, which produces 97% of the world's supply. Other opal deposits are found in Brazil, the western U.S., Mexico, and Hondouras. 

History

Opal is a breathtaking iridescent color-changing stone that has a different hue with each varying angle of observation. Australian Opal is the most well known variety of opal, as they produce such a large percentage of the world's supply. Dive into the world of Australian Opals with our Australian Opal Information Guide!

Opal’s color range and pattern help determine its value. Opal ranges from clear to white, gray, red, orange, yellow, green, blue, magenta, rose, pink, slate, olive, brown, and black. Of these hues, the reds against black opal are the rarest, whereas white and green opals are the most common.

Fashion

The October birthstone, opal has a shifting play of kaleidoscopic colors and is unlike any other gemstone. Are you unique and unlike any other? If so, opal is your stone. Opals can be worn as a fun piece, pairing well with every color as it plays off of whatever you are wearing! Sparkle and shine with the hues of opal jewelry. 

Formation

Opal is the non-crystalline form of the mineral silica. Unlike any other gemstone, it forms in lumps of silica. Silica gel fills the crevaces of rocks and, as water evaporates out, the silica is deposited as tiny spheres into the rock. Unique from any other gemstones, opal can contain up to 20% water in its silica surface!

Cleaning & Care

Opals should be worn with care and treasured. Avoid exposure to heat, contact with chemicals, and protect from scratches and harsh blows. To clean your opal, gently scrub with a soft toothbrush, mild dish soap and warm water. Ultrasonic and steam cleaners should never be used on an opal. Due to the delicate nature of opals, they are not recommended to be worn daily in jewelry that is subject to routine wear and tear. 

Treatments

Opals are often treated with colorless oil, wax, or resin to bring out their iridescent colors. This mimics the effect of water on the surface of an opal, but lasts indefinitely rather than evaporating off. 

MOH'S Hardness

5.0 - 6.5

Scratch resistance through the ability of a harder material to scratch a softer material.

Specific Gravity

2.15

The relation between the density of any substance and the density of water.

Refractive Index

1.37 - 1.47

The ratio of the velocity of light in a vacuum to its velocity in a specified medium.