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Klimmer
Mountain climber
San Diego
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Jan 16, 2010 - 11:02pm PT
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Thanks you guys. I'll have to come up with a mineral eventually that will stump you guys, although I will admit I can easily be stumped. I mean how many minerals are there something like 4000 + ?
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tuolumne_tradster
Trad climber
Leading Edge of North American Plate
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Jan 16, 2010 - 11:09pm PT
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In 1998 NASA started the Spaceguard Near-Earth Object Survey to identify objects, like asteroids & comets > 1 km in diameter that orbit close to the Sun. The National Academy of Sciences (NAS) is researching methods to divert objects like this that could impact the earth during the next 100 years. Such objects would have ~1 billion tons of mass. Traveling at 30 km/sec, it would have explosive power equivalent to 100 billion tons of TNT. One option being evaluated is to detonate a nuke near an incoming asteroid to divert &/or fragment it.
-Reference: Science & Technology Review, December, 2009. A publication of Lawrence Livermore Laboratory.
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tuolumne_tradster
Trad climber
Leading Edge of North American Plate
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Jan 16, 2010 - 11:12pm PT
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Minerals: OK thanks for the hints...black tourmaline
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Minerals
Social climber
The Deli
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Jan 16, 2010 - 11:13pm PT
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Yeah, impacts are big enough to even put a dent in the geologic time scale… at 65!
http://en.wikipedia.org/wiki/Chicxulub_crater
How ‘bout that iridium layer, Klimmer?
Think I originally read about it in a McPhee book.
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tuolumne_tradster
Trad climber
Leading Edge of North American Plate
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Jan 16, 2010 - 11:25pm PT
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Minerals: check out the pegmatitie counter top we just installed at our cabin in Monte Rio.
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Klimmer
Mountain climber
San Diego
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Jan 16, 2010 - 11:29pm PT
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Yep, the iridium layer that the geologist father and son team discovered and led them to the theory of the impact demise of the dinosaurs at 65mya is well represented in the above mentioned movie. They are interviewed and show the layer and what it looks like, and how they made the discovery. Very cool.
OK, lets mix it up. Here is a mineral property that is very cool to look at Flourescence!
I will make it easy.
This type local for the following flourescent minerals is World Famous and here in the good ol USA.
3 questions:
What is the name of the famous type local for these well known flourescent minerals in the following image? These minerals are all from the same famous local.
What is the mineral that floureses bright orange in these rocks?
What is the mineral that floureses bright green in these rocks?
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tuolumne_tradster
Trad climber
Leading Edge of North American Plate
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Jan 16, 2010 - 11:39pm PT
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Willemite/Calcite
Franklin, New Jersey
Orange red calcite, Green willemite
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Klimmer
Mountain climber
San Diego
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Jan 16, 2010 - 11:50pm PT
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Ding. Ding. Ding.
You are correct.
I love flourescent minerals.
I really love it when I find a mineral that looks beautiful in natural light, along with really interesting crystal habit, and then turn on my "Way Too Cool" powerful short wave UV lamp and the color just pops! Major wow factor! Multiple bangs for the one find or purchase.
I think Fritz posted about TG&MS already. I'm getting excited just thinking about it. TG&MS, the finest Gem and Mineral Show in the World.
We are blessed every year with the Tucson show.
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Minerals
Social climber
The Deli
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Jan 17, 2010 - 12:08am PT
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Wow, cool stuff! Neat fluorescence and sweet diagrams of Chesapeake Bay, especially the cross section! This planet could use another good knocking…
The rock on the left is granodiorite. The rock on the right is aplite (dike). What rock type/texture describes the vertical band of rock in the center of the photo? What is going on here?
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Minerals
Social climber
The Deli
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Jan 17, 2010 - 12:23am PT
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In general terms, what kind of rock is this? (Photo is a close-up)
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Klimmer
Mountain climber
San Diego
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Jan 17, 2010 - 12:32am PT
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Total stab in the dark . . .
1st photo, seam or dike of plagioclase?
2nd photo, looks like it is being squeezed and sheared, with another mineral type forming between, so in the generalist of rock types - Metamorphic Rock.
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Minerals
Social climber
The Deli
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Jan 17, 2010 - 12:37am PT
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Correct on the second photo in that it is a metamorphic rock. What kind of metamorphic rock – protolith?
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Minerals
Social climber
The Deli
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Jan 17, 2010 - 12:37am PT
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What is this mineral?
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Minerals
Social climber
The Deli
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Jan 17, 2010 - 01:21am PT
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Looks like some nice countertop material there, Tradster! Is the black mineral tourmaline or big biotite? I bet there’re some cool textures in the feldspars. We just have regular granite with smoky quartz in the kitchen here, but it’s got a bit of a wavy foliation to it here and there. (Got tired of freezing my ass off and getting sick in the cold so rented a room at the end of last month…)
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tuolumne_tradster
Trad climber
Leading Edge of North American Plate
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Jan 17, 2010 - 01:22am PT
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my guess for the mineral 2 posts above is sphalerite
the protolith for the metamorphic rock is a tough one...my WAG is a porphyritic volcanic rock
the black minerals in our countertop pegmatite are biotite & hornblende. I'll look next time I'm up there to see if there is any tourmaline and take some close up photos. Definitely some very cool twinning and exsolution (perthitic?) textures in the feldspars.
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Minerals
Social climber
The Deli
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Jan 17, 2010 - 01:36am PT
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It does look like sphalerite, but it’s in a different set of minerals. The photo was taken near May Lake, Yosemite.
The orange color in the metamorphic rock is surface staining and your WAG is correct – porphyritic metavolcanics east of Tioga Pass.
Yeah, perthite (perthitic feldspar/perthitic texture/etc.) and maybe some graphic textures as well… Good stuff!
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tuolumne_tradster
Trad climber
Leading Edge of North American Plate
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Jan 17, 2010 - 01:47am PT
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Minerals: are these photos of minerals you are posting part of your personal mineral collection?
I had a very nice mineral collection that I had accumulated over ~20 years that got stolen from a storage space. I miss that mineral collection.
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Minerals
Social climber
The Deli
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Jan 17, 2010 - 02:16am PT
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Tradster, that sucks that your mineral collection was stolen! You have to wonder when someone steals ROCKS! Did you have any valuable samples?
Pretty much all of the photos that I have been posting were taken out in the field, with the exception of the wollastonite sample and the following garnet/tourmaline sample. I have over a ton of rock in storage (literally) and maybe I can find a few more samples to dust off and photograph. A lot of it is pretty buried.
A mini collection:
Pebbles on the tailgate for show-and-tell with my friends last June. Most of the minerals should be relatively obvious.
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