0
Opals
Opal is a non-crystalline solid which is not really a mineral but is actually a mineraloid. It is often used as an accessory for jewelry because of its translucent characteristics. About 97% of the world’s opals are produced in Australia.
334 Questions
Opals can float in water because they have low density. However, not all opals will float as this depends on their specific density and porosity. It's always a good idea to test each opal individually if you plan on using water to differentiate between a synthetic or a simulant.
What chemical formula is opal made from?
Opal is a mineraloid gel. It is made, oddly enough, almost entirely of opal.
It is also completely free of birefringence, and has virtually no pleochroism.
Opal is basically silica. Saying opal is made of opal is like saying quartz is made of quartz, or tiger eye is made of tiger eye. It's the unique structure of the silica that makes it become opal. The Japanese have made a nice man made opal using silica and zirconium oxide.
Si02nH20
What element oxide makes up quartz and opal?
Silicon dioxide (SiO2) is the element oxide that makes up quartz and opal. Silicon dioxide is a compound composed of silicon and oxygen atoms and is the main component of these minerals.
The Olympic Australis Opal is believed to be the largest gem opal ever found, and it was found at Coober Pedy.
Found in 1956 at the "Eight Mile" opal field in Coober Pedy, South Australia, the Olympic Australis Opal was found at a depth of 30 feet and so named because the Olympic Games were being held in Melbourne at the time.
The Olympic Australis consists of 99% gem opal, with the remainder of 1% being the soil still attached to the stone. It weighs 17,000 carats (3450 grams) and is 280 mm long (11 inches) by 120 mm, by 115 mm. It was valued at AUD$2,500,000 in 2005.
Opals are mainly used for jewelry, ornaments, and collector specimens. They are also used for healing.
How much is a 2.5 carat opal worth?
The value of a 2.5 carat opal can vary significantly depending on factors such as the quality, color, clarity, and origin of the stone. In general, opals can range in price from a few dollars per carat for lower-quality stones to several hundred dollars per carat for high-quality stones. It is recommended to have the opal appraised by a professional to determine its exact value.
Australian black opals are the most valuable and widely known type of opal. Black opal is characterised by a dark body tone which can range from dark grey to jet black. (See the following chart). However this refers only to the general body tone of the stone, and is not related to the rainbow or spectral colours present in the opal. Some people expect a black opal to be completely black (in which case it would be completely worthless).
* http://www.opalsdownunder.com.au/articles/black.php
What is the density of an opal?
The density of opal typically ranges from 1.9 to 2.3 g/cm³, with an average density around 2.1 g/cm³. This can vary depending on the specific type and composition of the opal.
A mineraloid is a naturally occurring substance that lacks a crystalline structure, which distinguishes it from minerals that have a well-defined atomic structure. They may have a chemical composition similar to minerals but do not exhibit the same regularity in their internal arrangement of atoms. Amber and opal are examples of mineraloids.
Where do people sell black opal?
People typically sell black opal in jewelry stores, online marketplaces such as eBay or Etsy, specialized gemstone auctions, or through private dealers. It is important to ensure that the black opal is certified and authenticated before making any transactions to guarantee its authenticity and value.
Do opals contain a lot of water?
An Opal usually contain 4 to 9 per cent water but lower and higher values have been observed.
What is the genre for the opal deception?
The Opal Deception is a fantasy novel and falls into the subgenre of young adult fantasy. It is part of the Artemis Fowl series written by Eoin Colfer.
Why did opal write down and memorize the 10 things her daddy told her about mama?
Opal wrote down and memorized the 10 things her daddy told her about mama because she wanted to keep her mother's memory alive after her death. The list served as a way for Opal to remember her mother's characteristics and qualities, and it helped her feel close to her mother even though she was no longer physically present.
Opal promised to work at the pet store sweeping the floor and dusting the shelves.
Where can you buy opal jewelry?
You can fossick for opals in Australia. In the United States several opal mines are open to digging. Sometimes opal claims are available for sale in the Virgin Valley area of Nevada, known for producing the best opal in the United States.
Black opal can be very expensive, only low grade black opal is sold by kilo weight. This low grade is called potch and colour which means that maybe bit of colour might be in this rough black opal I have seen parcels sold for $200 per kilo but it has no colour. Good kilo bucket of rough black opal would cost around $5,000 .00 Black opal is rated by body tone N1 for deep black colour, and N4 for light black colour. So for $5000 per kilo, dont expect N1 body tone. Black opal is sold by carat, and rare patterns are worth $5,000 to $20,000 per carat; especially red fire harlequin pattern n1 body tone, and over brighness rating of 4.
Opals have a special characteristic which makes the gem a rainbow-like iridescence that changes colors when turned at different angles.
it is round ( like and egg), it is really smooth all around it, it comes in: clear through white, gray, red , orange, yellow, green, blue, magenta, rose, pink, slate, olive, brown, and black. it is found in Australia. a opal is an amorphous form of silica related to quartz, a mineraloid form, not a mineral.
What is opal birthstone used for?
Opal is a noun, therefore it is an object and cannot have a past tense. Only verbs can have past tenses. Verbs are actions that you can do, such as walk
