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If the basalt flow contains air bubbles and pockets and there is a spring that contains silica then the silica can deposit into the air bubbles (the air bubbles are known as Amygdaloidal basalt or vesicles) If the silica deposits slowly and the conditions are correct then precious opal can form. Two examples of this would be in California at the Nowak and the Barnett mines.
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Are opals made from volcanoes?
The volcano itself does not make the opal. The lava, be it Rhyolite or Basalt has air bubbles in it (called vesicles) these air pockets of many differing sizes are the future home of the opals. After time wheh the lava cools any silica rich springs begin a slow deposition of silica which, if the conditions a correct, will form common and precious opal. The volcano creates the matrix (or host rock) of the opal.
What is the chemical name for opal?
Opal is a form of silica, amorphous and hydrated: SiO2.nH2O.
Why is the mineral opal referred to as a mineraloid?
Opal is an amorphous form of silica related to quartz, a mineraloid form, not a mineral. A mineraloid is a mineral-like substance that does not demonstrate crystallinity.Now you get it?
Are there different kinds of opal?
The types of Opal that i am familiar with are White Opal, Fire Opal, Boulder Opal, Black Opal, Crystal Opal, Light Opal, Doublet Opal, Triplet Opal, Common Opal, Synthetic Opal, and Immitation Opal.
Is opal an intrusive or extrusive mineral?
Opal is not considered a rock but actually a mineraloid gel. It is deposited at relatively low temperatures. One of the characteristics if igneous rocks, sometimes called fire rocks, is that they are formed at high temperatures. Whether an igneous rock forms below ground, or on or near the surface, it's all about heat forming the rock. Opal cannot take its form under that kind of heat.
What is the form of Opal?
Opal has no definitive form. The word used to describe opal is "amorphous" which means: lacking definite form - having no specific shape.
Is opal similar to peridot?
No. Opal is an amorphous hydrated form of silica.
Are opals made from volcanoes?
The volcano itself does not make the opal. The lava, be it Rhyolite or Basalt has air bubbles in it (called vesicles) these air pockets of many differing sizes are the future home of the opals. After time wheh the lava cools any silica rich springs begin a slow deposition of silica which, if the conditions a correct, will form common and precious opal. The volcano creates the matrix (or host rock) of the opal.
What is the chemical name for opal?
Opal is a form of silica, amorphous and hydrated: SiO2.nH2O.
Is an opal a rock?
No, it's actually a form of silica.
Why is the mineral opal referred to as a mineraloid?
Opal is an amorphous form of silica related to quartz, a mineraloid form, not a mineral. A mineraloid is a mineral-like substance that does not demonstrate crystallinity.Now you get it?
Are there different kinds of opal?
The types of Opal that i am familiar with are White Opal, Fire Opal, Boulder Opal, Black Opal, Crystal Opal, Light Opal, Doublet Opal, Triplet Opal, Common Opal, Synthetic Opal, and Immitation Opal.
Where are opals made?
Australian Opal are dug and cut both on the opal fields and in the city's. they are found in New South Wales (NSW) - The Home of Black Opal New South Wales produces most of the Opal of Australia. Lightning Ridge opal is the darkest and most valuable form of opal. White Cliffs, produces white or crystal opal in the form of 'seam White Cliffs is also noted for the production of 'opal pineapples' Queensland produces boulder opal, these occur in deposits in weathered sedimentary Cretaceous rocks in the west of the state Quilpie, Queensland the largest producer of boulder opal in the world Winton, Queensland Opalton, Queensland Yowah, Queensland home of the opal refered to as Yowah Nut, South Australia - The White Opal Fields South Australia has 4 working opal fields, Andamooka, Coober Pedy, Lambina and Mintabie. South Australia produces the largest amount of opal and this is known as milky opal. Coober Pedy produces most the world's white opal. Andamooka, South Australia Mintabie, South Australia Lambina, South Australia
What cause opal to be sad as she eats the littmus Lozenge?
Because it reminds her of her mom.
How many opal types are there?
There are 5 basic types of opal. These types are Peruvian Opal, Fire Opal, Girasol Opal, Common opal and Precious Opal.
Is opal an intrusive or extrusive mineral?
Opal is not considered a rock but actually a mineraloid gel. It is deposited at relatively low temperatures. One of the characteristics if igneous rocks, sometimes called fire rocks, is that they are formed at high temperatures. Whether an igneous rock forms below ground, or on or near the surface, it's all about heat forming the rock. Opal cannot take its form under that kind of heat.
How many types of opals are there?
There are 5 basic types of opal. These types are Peruvian Opal, Fire Opal, Girasol Opal, Common opal and Precious Opal.
