Opals are amorphous because they have no definitve shape. As an example, quartz has a specific crystal shape. Opals can be any shape.
A color change is only a chemical change if the change is permanent, if the color change is not permanent, then it is likely a physical change. Let's look at Iodine for example (that's pronounced Eye-oh-deen), it is a solid metal that is grayish in color in its solid state, however in its gas state it's a purple or violet color. Once it reverts to its solid state, it turns gray again. This is a PHYSICAL property of Iodine. If the color changed permanently to something else, it would be a chemical change.
The resulting color will be a lighter version of the saffron color. It will not change the hue at all. It will change the shade of the color.
Opals are composed of the natural mineral silica, and water. The water content varies from as little as 3% to 21%, but it normally contains 6% to 10%.
color change
The value of opals varies wildly as the play of color (fire) varies wildly. Opals do not have a fixed value such as gold and silver and the value is open to debate between the buyer and seller. Generally speaking.....if the opals are uncut and of moderate fire - they will not be very valuable.
No. When opals were first found in Australia, they were not thought to be opals because they were a milky white in appearance. Opals found elsewhere in the world were mostly black.
Pearls and opals are often described as milky white. Moonstone could also come in this color.
Opals are amorphous because they have no definitve shape. As an example, quartz has a specific crystal shape. Opals can be any shape.
Nobody MADE opals. They're mined out of the ground.
Opals cannot be used as foods. They are hard, precious stones.
Neither opals or any other gemstone will make you invisible.
Some opals are known as black opals, this is when they have a mainly black colour. In general a black opal is very dark blue and has flecks of other colours within
Three different types of Opal are found in Australia:Fire Opals are mined in South Australia near Coober Pedy.Black Opals are mined in New South Wales near Lightning Ridge.Boulder Opals are mined in the western Queensland.
No they do not shrink.
color change is when a color changes
Yes. Coober Pedy is still a major producer of opals.