One of the most unique gems in the world, opals, unlike other gems, can reflect colors of the rainbow by refraction due to the silica inside the stone. In addition, these gems are commonly found as, well, opaque thus giving them the ability to be a canvas for the play of colors. With these features, opals are like tiny capsules of the night sky with play of color acting as glittering stars.
For those looking to acquire some of these enchanting stones, opals can be a very personal experience as every opal is different and unique to the buyer. High value opals might be meaningless to you if you do not like the colors at play on the stone.
Here some general information and tips when you're out on your adventure to finding the perfect opal for you.
Black opals are the most expensive type of opal gems because the dark body tone which helps enhance the play of colors. Rare and precious, a high quality black opal with excellent plays of color can be worth more than all but the finest diamonds.
Crystal opals are the second most expensive and does have some transparency that makes them unique. The most common and least expensive are white opals; their creamy body tone does at time distract the shine of the colors.
Sometimes considered a class of their own, fire opals have some transparency but do not have any play of colors. Found in hues of orange to orange-red colors, fire opal stones are commonly cut into traditional gem cut facets.
The last, but definitely not least, are boulder opals. Boulder opals are basically dark ironstone with thin layer of opal on the surface. The opal veins on the ironstone can make interesting designs with amazing play of colors.
Doublets and triplets are man-made that consist of a thin opal that is glued on a dark ironstone or sandstone. Generally, very cheap, doublet and triplet are used for jewelry as the back can be hidden. Only difference between the two is that triplets have an extra layer of plastic or glass of protection.
Opals from Welo, Ethiopia - newly discovered deposits - are generally cheaper than those from Australia. Although slightly cheaper, black opals from Ethiopia are just as stunning as those from Australia.
For those looking value when choosing the color of play, the order goes as red, orange, yellow, green, blue, indigo and violet. Red being the most expensive, while violet being the least expensive.