The prevalence of dark minerals such as pyroxene and olivine cause basalt to have a dark gray to black color.    From Wordnik.com.  [Yahoo! Answers: Latest Questions] Reference

Usually a blend of lightweight silicates – feldspar, olivine, pyroxene.    From Wordnik.com.  [Deception Point]

In the granite, pyroxene has been partially converted (supra-solidus) to Fe-rich biotite.    From Wordnik.com.  [Granophyre.html] Reference

Moondust is also rich in iron, calcium and magnesium bound up in minerals such as olivine and pyroxene.    From Wordnik.com.  [Boing Boing: January 29, 2006 - February 4, 2006 Archives] Reference

BRONZITE, a member of the pyroxene group of minerals, belonging with enstatite and hypersthene to the orthorhombic series of the group.    From Wordnik.com.  [Encyclopaedia Britannica, 11th Edition, Volume 4, Part 3 "Brescia" to "Bulgaria"] Reference

This region of the Earth's interior is thought to be composed of peridotite, an ultramafic rock made up of the minerals olivine and pyroxene.    From Wordnik.com.  [Structure of the Earth] Reference

The one characteristic they have in common is the inclusion in the fabric of black shiny specks (the volcanic minerals amphibole or pyroxene).    From Wordnik.com.  [Interactive Dig Sagalassos - Survey Report 15: Suburban] Reference

Most chondrules are 0.5 to 2 millimeters in size and are composed of olivine and pyroxene, with smaller amounts of glass and iron-nickle metal.    From Wordnik.com.  [New Notions of Earth's Origins Needed, Says Geochemist] Reference

Most of them contained crystals of felspar and pyroxene.    From Wordnik.com.  [To the Gold Coast for Gold A Personal Narrative in Two Volumes.—Volume I] Reference

There is also a small amount of hematite, pyroxene and sericite.    From Wordnik.com.  [The Long Labrador Trail] Reference

The greyish blue amygdaloid contains fendilated crystals of pyroxene and mesotype.    From Wordnik.com.  [Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 3] Reference

A coarse dark green rock whose principal constituents are pyroxene plagioclase and magnetite.    From Wordnik.com.  [The Long Labrador Trail] Reference

It is supposed to have formed by the alteration of olivine and pyroxene in the igneous rocks.    From Wordnik.com.  [The Economic Aspect of Geology] Reference

This crater is rich in olivine, which, like pyroxene detected by the M3 recently, contains iron.    From Wordnik.com.  [Signs of the Times] Reference

These rocks are composed predominantly of the minerals plagioclase feldspar, amphibole, and pyroxene.    From Wordnik.com.  [Featured Articles - Encyclopedia of Earth] Reference

I have found in it neither amphibole nor pyroxene, but some small white points, which seem to be feldspar.    From Wordnik.com.  [Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 1] Reference

Both are common alteration products of magnesian silicate minerals such as olivine, pyroxene, and amphibole.    From Wordnik.com.  [The Economic Aspect of Geology] Reference

Here it is believed to be an alteration product of diopside (lime-magnesia pyroxene) in a contact-metamorphic silicated zone.    From Wordnik.com.  [The Economic Aspect of Geology] Reference

Major Long and Dr. James, trap-formations (bulleuses dolerites and amygdaloids with pyroxene) also border the plains or basin of the.    From Wordnik.com.  [Travels to the Equinoctial Regions of America] Reference

Continued temperature decreases change the minerals dominating the composition of the rock from pyroxene, to amphibole, and then biotite.    From Wordnik.com.  [Featured Articles - Encyclopedia of Earth] Reference

The latter occurs at low temperatures when rocks rich in the minerals olivine and pyroxene react chemically with water, releasing methane.    From Wordnik.com.  [BBC Blog Network] Reference

In these occurrences the tungsten mineral is almost invariably scheelite, and is associated with calcite, garnet, pyroxene, and other silicates.    From Wordnik.com.  [The Economic Aspect of Geology] Reference

As magma moves up toward the surface, it loses water and the amphibole reacts, forming a rim containing plagioclase, pyroxene, and oxide minerals.    From Wordnik.com.  [Latest Articles] Reference

Feldspar with a basis of souda (compact feldspar) forms, with diallage, the euphotide and serpentine; with pyroxene, dolerite and basalt; and with garnet, eclogyte.    From Wordnik.com.  [Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 3] Reference

The close connection observed in the strata of Parapara, between greenstone, amphibolic serpentine, and amygdaloids containing crystals of pyroxene; the form of the Morros of.    From Wordnik.com.  [Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 3] Reference

Their nucleus is almost as hard as basalt, and they are intermingled with little cavities, owing to bubbles of gas, filled with green earth, and crystals of pyroxene and mesotype.    From Wordnik.com.  [Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 2] Reference

There is pyroxene and plagioglase as well as evidence of olivine crystals. ".    From Wordnik.com.  [The Dig]

It is very rich in olivine and pyroxene.    From Wordnik.com.  [Lunar regolith] Reference

Plagioclase is white and pyroxene is brown.    From Wordnik.com.  [Lunar regolith] Reference

Steel volcanic glass, pyroxene, amphibole (H 5-6).    From Wordnik.com.  [volcanic ash hazards and ways to minimize them] Reference

Mr. Karsten, to the pyroxene augite.    From Wordnik.com.  [Travels to the Equinoctial Regions of America] Reference

M. Hauy considers it a variety of the pyroxene.    From Wordnik.com.  [Travels to the Equinoctial Regions of America] Reference

Small grains of secondary pyroxene are numerous.    From Wordnik.com.  [The Long Labrador Trail] Reference

"And not a trace of cleavable pyroxene," said he.    From Wordnik.com.  [Punchinello, Volume 1, No. 20, August 13, 1870] Reference

A variety of the pyroxene.    From Wordnik.com.  [Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 1] Reference