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2. Peridot - Wikipedia

   en.wikipedia.org/wiki/Peridot

   Peridot olivine is the birthstone for the month of August. [17] Peridot has often been mistaken for emerald beryl and other green gems. [18] Noted gemologist G.F. Kunz discussed the confusion between beryl and peridot in many church treasures, most notably the "Three Magi treasure" in the Dom of Cologne, Germany. [19] [1]

3. Olivine - Wikipedia

   en.wikipedia.org/wiki/Olivine

   The mineral olivine (/ ˈ ɒ l. ɪ ˌ v iː n /) is a magnesium iron silicate with the chemical formula (Mg,Fe) 2 Si O 4.It is a type of nesosilicate or orthosilicate.The primary component of the Earth's upper mantle, [9] it is a common mineral in Earth's subsurface, but weathers quickly on the surface.

4. Peridotite - Wikipedia

   en.wikipedia.org/wiki/Peridotite

   Kimberlite: formed in volcanic pipes and at least 35% olivine [9] Kimberlite is a highly brecciated variant of peridotite formed in volcanic pipes and is known for being the host rock to diamonds. Unlike other forms of peridotite, kimberlite is quite rare. [10] Pyroxene peridotite: From 40% to 90% olivine and less than 5% hornblende

5. Mafic - Wikipedia

   en.wikipedia.org/wiki/Mafic

   Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include basalt, diabase and gabbro. Mafic rocks often also contain calcium-rich varieties of plagioclase feldspar. Mafic materials can also be described as ferromagnesian.

6. Nephrite - Wikipedia

   en.wikipedia.org/wiki/Nephrite

   Nephrite jade is an ornamental stone used in carvings, beads, or cabochon cut gemstones. Nephrite is also the official state mineral of Wyoming . Nephrite can be found in a translucent white to very light yellow form which is known in China as mutton fat jade, [ 1 ] in an opaque white to very light brown or gray which is known as chicken bone ...

7. Anorthosite - Wikipedia

   en.wikipedia.org/wiki/Anorthosite

   The mafic mineral in Proterozoic anorthosite may be clinopyroxene, orthopyroxene, olivine, or, more rarely, amphibole. Oxides , such as magnetite or ilmenite , are also common. Most anorthosite plutons are very coarse grained ; that is, the individual plagioclase crystals and the accompanying mafic mineral are more than a few centimetres long.