What is a common opal?

What is a common opal?

“Common opal,” sometimes known as “potch”, is a variety of opal that does not exhibit the flash and “play-of-color” seen in precious opal. However, common opal occurs in a variety of beautiful colors that includes a range of wonderful pastels. Common opal is found in a greater range of colors than most other gems.

How rare is common opal?

How rare is opal? Silica is one of the most common minerals on the planet, but precious opal is very rare – far more rare than diamonds. Precious opal is rare because the natural processes that create it rarely occur. Most (at least 95\%) of the opal found by miners is common opal without gem colour.

What makes an opal precious?

The value of an opal depends on many factors. The type of opal, body tone, brilliance, pattern, colour bar thickness, the play of colour, and faults all play important roles in determining the value. Other important factors include the quality of the cut & polish, and the size of the stone.

How do I know if I have an opal rock?

Most genuine solid opals have an irregularity in this area – curved or bumpy due to their natural formation – whereas a man-made stone will be perfectly flat because the two sections are flattened so they can be glued together. Be especially wary if the opal is set in jewellery and you cannot see its back or side.

Are opals worth more than diamonds?

Getting your hands on opal is easy, but finding gem-quality opal is another story. Diamonds, on the other hand, fetch a high price even for the most low-quality diamonds. Because the value of most diamonds will be higher than opals, while high-quality opals are rarer than diamonds.

How much is raw opal worth?

Black Opal prices vary from roughly $30 per half carat, up to $1,500 per carat. This is only the . 5-1 carat range. High quality Black Opals weighing 5-10 carats can cost up to $50,000.

What are the prettiest opals?

Some of the finest, most-valuable opals in the world include:

• Fire of Australia. Considered the finest uncut opal, it is valued at close to $900,000.
• The Virgin Rainbow. This $1 million opal is the world’s most expensive.
• Aurora Australis.
• The Queen.
• Pride of Australia/Red Emperor.
• The Flame Queen.

What is the difference between precious and non-precious opal?

What is the difference between precious and non-precious opal? Precious opal shows a play of spectral colours though the stone whereas common opal does not. Common opal is usually opaque to translucent and brownish orange in colour, however it can come in any colour, some of which are quite attractive.

What is the difference between Opal and common opal?

In common opal, the cristobalite spheres are of somewhat random sizes and randomly distributed throughout the opal mass. The only effect on light is the ‘opalescence’ or seeming glow of some clear opal, or a solid color of some sort, most often white. Common opal, is of course, more common than precious opal.

What kind of opal is purple in color?

Here’s the GIA lab report for the stone on the left. Mexico produces a unique purple common opal known as “ Morado ” that can be made into beautiful cabochons. Much of the fire opal mined in Mexico could be considered “common opal” because it lacks play-of-color.

What does opal look like in Nevada?

Nevada produces much common opal that ranges from bright white to buttery yellow in color. These sometimes contain black dendrites and moss. Many specimens are fluorescent, producing a bright green glow under an ultraviolet lamp. Much of Nevada’s opal is subject to crazing and color changes after mining.