There’s also a fully searchable index covering the complete thin section set, listing for each sample its locality, the anticipated major minerals, a brief generalized geologic environment description, and where appropriate, the nature of any unusual element enrichments.
Note: Depending on the speed of your internet connection, it could take a minute or two for the images to load.
left image: unpolarized light; right image: under crossed polarizers; use slider in center to view more of either image
sample: K-65 (covered and yellowing thin section from Univ. Arizona petrology collection [unfortunately, the original billet & hand sample appear to be lost], Krantz collection, sample K-65)
locality: Kaltes Tal, Bad Harzburg, Harz Mtn. region, Niedersachsen, Germany.
rock type: mica peridotite (as small lenses in norite). Also known locally as “glimmerite”.
major mineralogy: Based on petrography, predominately forsterite and red Ti-rich(?) biotite, with gray spinel and minor oxide (believed to be ilmenite).
accompanying videos: Short videos featuring the mineral associations and optical properties of the biotite in this thin section offer a more detailed look at this sample.
| mineral | PPL (lower polar rotation) |
PPL (stage rotation) |
XP (stage rotation) |
optic figure (stage rotation) |
|---|---|---|---|---|
| biotite PPL: pale tan-orange/red-orange/deep brown-red pleochroism, moderate relief; XP: birefringence largely masked by body color of mineral, mottled extinction; with spinel, forsterite and an opaque oxide (covered thin section) |
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previous page (samples FKM-351 to FKM-375)
This “add photo(s)” image is just a placeholder in advance of adding new samples, so check back periodically to see my progress.