Kimberlitic rock is generally bluish, greenish or black. Typically in So.Africa, our epitomical mother, it's blue or bluish-green (unweathered, ie). The presence of olivine (magnesium iron silicate, -peridotite associated) can lend towards the green, etc ...
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Go here for a "Virtual field trip" to the Rockies, w/ actual photos of kimberlite hand-samples, and kimb.-outcroppings (from RMAG):
rmag.org
(RMAG = "Rocky Mountain Association of Geologists")
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Learn about IGNEOUS ROCKS AND PROCESSES:
arbuckle.utulsa.edu
Classifications:
Dark colored [kimberlite] - A Peridotite contains Olivine, Pyroxene, and some Calcium Plagioclase Feldspar.
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Kimberlite- A highly serpentinized porphyritic peridotite, commonly brecciated, which occurs in vertical pipes, dikes, and sills. It is the principal original environment of diamond, but only a small percentage of the known kimberlite occurrences are diamondiferous. See also: "blue ground"; "yellow ground". The name is derived from Kimberley, South Africa. (from: imcg.wr.usgs.gov )
Blue ground: Unoxidized slate-blue or blue-green kimberlite, usually a breccia (as in the diamond pipes of South Africa) that is found below the surficial oxidized zone of "yellow ground."
"Kimberlites are serpentinized mica peridotites that contain a variety of high pressure minerals, including diamonds."
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Olivine:
luigi.calpoly.edu
geology.wisc.edu
mineral.galleries.com
minerals.gps.caltech.edu
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Gordon, you were wanting info re. AB fault structure, etc-- try this link to learn a lil about just that:
geop.ubc.ca
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Cheers,
-j
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