|Mineral class||Silicates : Nesosilicates : Zircon - tantalite group.|
|Habitus||Short prismatic dipyramidal crystals or irregular grains.|
|Cleavage||Imperfect, uneven to conchoidal fracture.|
|Color||Colorless, red, brown, yellow, green or gray. Transparent to opaque.|
|Luster||Vitreous, adamantine to greasy.|
|Occurance||In granites, pegmatites and nefeline syenites.|
|Notes|| Often radioactive due to small amounts of thorium and uranium.
(Up to 14 %) |
Zircon is often metamict (no crystal structure) because of the radioactivity thats destroyed the internal structure.
Zircon is a very good mineral to measure the age of rocks. It encapsules the uranium and the rest product, led, so it is possible to measure the age of different layers in a zircon crystal. The oldest zircon found in Sweden is 3300 million years old.
Flourescent in UV-light.
|Locations|| A common mineral in microscopic amounts.|
| To silicate index.
|| Mineral group index.
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