Australian Black Opal – Is It Solid Opal or A Doublet?

Australian Opal – Is It A Solid Opal or a Doublet

A few weeks ago I was out at the opal fields in Lightning Ridge, New South Wales when I cam across a rather interesting solid Opal. I was looking through thousands of piece of beautiful Australian black opal looking for something interesting, something unique.

This is how everyone checks out precious gemstones right? In a fancy shop with white gloves on? Nah, on the bonnet of an old dirty Holden ute, sorting through a coffee jar full of colorful opal and an orange juice in hand, because looking at opal can be thirsty work in the heat!

After looking through a bucket load of rough opal, one particular piece caught my eye. At first I was sure it was an opal doublet instead of a solid opal, made by gluing colorful opal onto a black base. Opal doublets are worth considerable less than solid opal, and sometimes they can be accidentally mixed up in a parcel of solid opal. Below is a picture of the solid opal and to the right is a diagram of how an opal doublet is made. The key to identifying them is the straight line between the black backing and the colourful opal. In nature, this line is never perfectly straight.

After a closer magnified look through a 10x loupe, I discovered that it was in fact a natural solid opal. The border between the natural precious opal (The color) and the black potch was so perfect to the naked eye that it looked like a straight line. Under magnification however it was obvious that there were small etches of potch into the color. This meant that this opal had to be natural.

This piece of Opal is going into my collection for reference. It is not very often that you something like this, where nature has created something that is almost identical to an opal doublet. It is a bit of a mystery as to how solid opal forms underground and why there are sections of black opal with color on top. This stone is just something so unique that I have to hold onto it.