Kristal-MineralTGS7113 - 2 SKS teori

by:

Dr. hil. gendoet hartono

Semester 1, 2018-2019

How are minerals formed?

The type of mineral that forms depends on the elements present in the area and the temperature and pressure.

Many minerals form from magma, which is molten rock inside Earth. As magma cools, the atoms join together to form different minerals.

Minerals also form from lava, which is molten rock that has reached Earth’s surface.

Many minerals form by metamorphism.

High temperature and pressure within Earth cause new minerals to form as bonds between atoms break and reform with different atoms.

How are minerals formed?

Minerals also form from solutions.

Water usually has substances dissolved in it. As it evaporates, these substances form into solids and come out of solution, or precipitate.

As hot water cools, dissolved substances may precipitate out of solution.

How are minerals formed?

Bahan galian magmatik adalah bahan galian

yang terbentuk akibat dari magma primer

yang bersifat ultrabasa lalu mengalami

pendinginan dan pembekuan sehingga

terbentuklah mineral-mineral tambang.

Endapan magmatis dapat terjadi karena

kristalisasi magma, segregasi, regregasi,

injeksi dan syngenetik. Contoh bahan galian

tipe ini adalah intan, korundum dan kromit.

SISTIM MAGMATIK

Bahan galian pegmatit adalah bahan galian

yang terbentuk dikarenakan hasil injeksi

magma, kristalisasi dari suatu magma

menyebabkan suatu perubahan konsentrasi

dari bahan-bahan uap. Sifat dari bahan galian

pegmatit adalah

• seperti dike

• kristal mineral sangat besar

• bersifat asam

• jenis mineral yang ditemui antara lain

kuarsa, ortoklas dan mika.

Contoh bahan galian pegmatit antara lain

besi, topaz, ruby, Au, Al, Li dan Sn.

See u in final test….