KDF-TX
Joined: 22 Jan 2008
Posts: 79
Location: Texas
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 Posted: Mar 12, 2010 12:49 Post subject: Re: Collection of Kevin Farrell |
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Pete, I keep calling you Peter, sorry.
This label thing has me questioning many in my collection... "Ex ***** ***** Collection" and localities, not to mention the species.
I did buy a specimen just for the label a few times. One I recall had the locality as Hecho, Mexico.
99% of my collection were bought for under $100. Of the 99% probably 75% under $50 with most of those under $20. I started buying in the early 1970s when I got my first job. I have over 500 in a database (not including the flats under my bed and in a storage building and barn and all the petrified wood/palm).
I have kept my collection to the Americas. I don't know why, but that's how I started it and kept going.
Here's photos of one I purchased off Ebay (I rarely do Ebay anymore except from a very few trusted). I was curious to see the COA. This is what I got. Opinions?
Kevin
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6051 Time(s) |
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| limonite psuedo after pyrite, collected 1946, Dana Location |
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6052 Time(s) |
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Pete Richards
Site Admin
Joined: 29 Dec 2008
Posts: 828
Location: Northeast Ohio
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| Posted: Mar 12, 2010 14:26 Post subject: Re: Collection of Kevin Farrell |
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| KDF-TX wrote: | Thanks GneissWare!
Peter, I've looked up babingtonite and hedenbergite:
hedenbergite is black, dark green, green-brown; brownish green in thin section.
babingtonite is dark greenish black.
I don't see hedenbergite listed on Mindat in Passaic Co.
I realize it would be a guess by a photo... what is the black in the middle photo?
It's dull black and I don't see a green tint.
Thanks, Kevin |
Those descriptions are good and reasonable. Hedenbergite, when it's in very thin hairs like it is in my photo, appears white, even though it would probably be dark if it were thicker. I'm not surprised that hedenbergite does not appear in the Mindat list for Passaic County - these hairs were earlier identified as something else, I think as acmite, which is a synonym for aegirine. But the identification as hedenbergite was done by a highly accomplished professional structural mineralogist, it's been published in several peer-reviewed papers, and I think there's no doubt about it. Mindat will catch up eventually.
As for the black in the middle photo, it's hard to see much detail, but it appears dull, earthy, and not particularly crystal-shaped. I don't know what it is - perhaps a chlorite mineral, perhaps a manganese oxide. But without a closer view of it, I can't see it as babingtonite.
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Collecting and studying crystals with interesting habits, twinning, and epitaxy |
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