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I've heard that during the accretion of proto-planets that formed the earth, 60 minerals were created through the reactions of atoms and molecules in the nebula.

Do these first minerals still make up Earth?
Do we have more minerals? If so, how and when were they created?

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This is a very interesting topic that in the past several years has reached the spotlight because of the work of Robert Hazen on the concept of "mineral evolution".

Minerals are basically just inorganic compounds: you take several elements, arrange them in certain ways and you get minerals. Thus, the minerals will be mostly determined by what's available to them in term of chemical elements. The solar nebula in Earth's area was composed of very few major elements: Fe, Si, Mg, Al, O, C, etc. There are not many ways you can arrange this limited number of elements, and the mineral diversity was rather small. You cite the number 60. Could be more, could be less, but it sounds about right.

With time, certain processes on Earth (magmatic, metamorphic, metasomatic, hydrothermal, you name it) preferentially move certain elements relative to others. This causes redistribution of elements in space, enriching and depleting certain elements in various areas. Elements that were previously present only in trace amounts and did not form minerals of their own may be concentrated so that they do.

This is a time dependent process, hence the name "mineral evolution". This is a nice figure that sums things up:

enter image description here

You can read more about it in Hazen's website (from which I took the above figure): http://hazen.carnegiescience.edu/research/mineral-evolution

Be careful though when searching for "mineral evolution" online - you usually get more results of pseudoscientific and creationist websites rather than actual science.

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  • $\begingroup$ 1. The solar nebula in Earth's area was composed of very few major elements. Does major just mean elements that are in large quantities on earth? 2. Does that mean that the increase in minerals was due to Earth physically redistributing elements already present at Earth's formation and thus forming new minerals, rather than new minerals (or elements) arriving from outer-bodies. 3. Do these original minerals made in space still exist in earth, or where they re-formed into different minerals through differentiation on Earth? $\endgroup$ – G. Gip Jul 9 '16 at 10:04
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    $\begingroup$ 1. yes, 2. yes, exactly (excluding H2O and hydrated minerals which is still debatable), 3. mostly. some minerals that are common in meteorites, particularly reduced minerals (e.g. carbides and native elements) or silica-poor minerals (e.g. hibonite) are now extremely rare on earth and occur only in very specific cases. But most minerals you find in meteorites are also common in Earth (olivine, pyroxene, etc). $\endgroup$ – Gimelist Jul 9 '16 at 10:17
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Minerals are naturally occurring chemical compounds composed of elements. Much of these elements were originally deposited with the earth saw formed. However, meteorites and asteroids have carried new mass onto the earth.

It is true some elements are too heavy to have been created by the Sun's fusion process. These heavier elements would have been created by other processes like various types of cosmic explosions.

Mineral creation is an ongoing process on the earth. So mineral creation is happening today. One example would be volcanic vents at the sea floor creating metal sulfide minerals like ZnS - sphalerite and PbS Galena.

Earth processes are constantly reworking existing rocks and minerals.

Copper Porphyry deposits have a igneous intrusion and the fluids from the intrusion flow into surrounding rock dissolving and redepositing minerals, creating a super-gene enrichment zone. At the deposit in Tsuemb Africa, a secondary super-gene enrichment zone was created by faults carrying surface water downward into the deposit.

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