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Fritz
Trad climber
Choss Creek, ID
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Topic Author's Reply - Apr 7, 2015 - 12:11pm PT
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I'm afraid these photos are not going to look as good as the above crystal.
Ludwigite is a fairly rare magnesium-iron borate mineral: Mg2FeBO5.
Ludwigite typically occurs in magnesian iron skarn and other high temperature contact metamorphic deposits. Of interest only to mineral collectors, although associated minerals like magnetite are worth mining on occasion.
I found these specimens high in Idaho's Lemhi Mountains a few years back.
Here's rectagular ludwigite crystals resting on magnetite & white marble from the same site.
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Cragar
climber
MSLA - MT
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Man, one of the cooler threads on this ROCK climbing site.
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L
climber
California dreamin' on the farside of the world..
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the albatross
Gym climber
Flagstaff
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Apr 14, 2015 - 02:53pm PT
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Sweet crystals everybody, thanks for sharing!
Here's a piece of Fluorite (China) from the collection.
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mouse from merced
Trad climber
The finger of fate, my friends, is fickle.
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Apr 14, 2015 - 04:48pm PT
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The other day I visited my friend John Decker, who likes to watch DVDs on the less-visited places so he can have something worthwhile to watch on his huge-screen 3-D mega-TV.
We viewed part of one which showed the Naica cave crystals.
These giants in the Cave of Crystals were created and grew in a subterranean water system in place for millions and millions of years.
The miners have pumped the water out to allow them access to minerals close by.
This removal of the water-bath is apparently causing the crystals to weaken and deteriorate as a result, according to the narration.
http://ngm.nationalgeographic.com/2008/11/crystal-giants/shea-text
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Fritz
Trad climber
Choss Creek, ID
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Topic Author's Reply - Apr 14, 2015 - 05:16pm PT
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Nice Rocks L & the albatross!
Mouse! That's a bummer that those giant Mexican Selenite? (I recall) crystals are now deprived of the moisture that allows them to grow & prosper.
Here's an eight-pound chunk of flurorite I hiked out of middle of nowhere Idaho a couple years back. Great exercise, since it was mostly downhill for 5 miles.
Love the green color, but the crystals are nice too.
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NutAgain!
Trad climber
South Pasadena, CA
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Apr 14, 2015 - 05:19pm PT
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tolman_paul
Trad climber
Anchorage, AK
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Apr 14, 2015 - 05:29pm PT
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Piece of quartz that I don't recall where I picked up but has been sitting on my desk for years.
I need to explore some old gold mines this summer to see what interesting specimens are in the tailing piles.
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L
climber
California dreamin' on the farside of the world..
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Apr 14, 2015 - 06:38pm PT
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Wow Fritz,
That's one beautiful piece of Fluorite!
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tuolumne_tradster
Trad climber
Leading Edge of North American Plate
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Apr 14, 2015 - 09:41pm PT
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Travertine deposit (aka Wedding Cake deposit) at The Cedars near Cazadero. Anyone interested in ultra-mafic rocks (mainly serpentinized peridotite) and deep-circulating alkaline springs should check this place out.
http://web.gps.caltech.edu/~als/research-articles/2013/morrill-gca-cedars-geochemi.pdf
Blue schist facies meta-greywacke knocker, Goat Rock Beach. Franciscan knockers make good sea stacks.
Soft sediment folding Franciscan radiolarian chert, Goat Rock Beach
Highly polished blue schist at Sunset Rocks (Mammoth rubbing stone analogous to modern Rhino rubbing stones in Africa)
Tar breccia near Vandenberg AFB
Vugular basalt, Ape Cave lava tube, Mt St Helens
Flow banding in Tuolumne Intrusive Series near Tenaya Lake. Resembles trough cross-bedding in fluvial sediments
Banded opsidian Panum Crater, Mono Lake
Ladder dike, Reid Slabs, Tuolumne River
Load structures in Eocene marine sediments near Carmel, CA
Rhyolite Breccia with lichen, Pinnacles
Vulcan's Anvil, Quaternary basalt, Grand Canyon
Tectonic breccia in Paleozoic limestone, Titus Canyon, Death Valley
Complexly folded Paleozoic strata, Grapevine Mountains, Death Valley
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Fritz
Trad climber
Choss Creek, ID
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Topic Author's Reply - Apr 21, 2015 - 05:38pm PT
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Wow! Love those photos of great geology-------and every other rock folks post here!
Here's some ripple marks, like those you see in stream-side sand or mud, or in sand dunes: hardened into limestone, uplifted to thousands of feet above sea level and turned 90 degrees. Biggest & best ripple-marks I've ever seen. Mustang Nepal, 2008.
Here's some nearby marine shell fossils. This area of the Himalayas was ocean floor until it was uplifted about 60-80 million years ago.
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this just in
climber
Justin Ross from North Fork
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Apr 21, 2015 - 06:00pm PT
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tuolumne_tradster
Trad climber
Leading Edge of North American Plate
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Apr 21, 2015 - 06:08pm PT
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Interesting that the highest elevation on the planet is composed of sediments that were deposited in an ancient (~500 MY) ocean bottom.
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the albatross
Gym climber
Flagstaff
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Apr 21, 2015 - 06:18pm PT
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This thread rocks!
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tuolumne_tradster
Trad climber
Leading Edge of North American Plate
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Apr 21, 2015 - 09:14pm PT
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Tunnel in volcaniclastic conglomerate
Smokey quartz crystals in cave restaurant near Vicosoprano, Switzerland
Feldspar megacrysts
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Darwin
Trad climber
Seattle, WA
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Apr 21, 2015 - 10:24pm PT
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I just love this thread. Thanks you all.
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Fritz
Trad climber
Choss Creek, ID
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Topic Author's Reply - Apr 27, 2015 - 09:05pm PT
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Apologies for being a little early, but I'm off to the Utah desert early tomorrow.
Chalcopyrite Peacock ore & Pyrite. I found this rock at an old copper mine on the Nevada-Utah border.
The blueish iridescent area is Chalcopyrite, (Copper iron sulphide) & the bright shiny area is Pyrite (Iron sulphide). There is also some quartz & some rusty iron stains on this nice specimen.
Chalcopyrite can look brassy, or be dark black, or rarely, if left in an acidic environment: can become the highly collectable iridescent Peacock Ore.
Of course mineral collectors with low morals do on occasion treat Chalcopyrite with acid to make fake Peacock Ore.
Close-up.
chalcopryite lower, pyrite upper.
Evening view east from the mine into Utah and the Bonneville Salt Flats.
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mouse from merced
Trad climber
The finger of fate, my friends, is fickle.
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Apr 27, 2015 - 09:22pm PT
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Have fun, Fritz!
Viva las rocas!
Kind of a non sequitur--they'll outlive us.Graffiti or art?
Stupid question. It's both.
The Trundlers with their hit song, Never Break Down, OldClymer on the sax.[Click to View YouTube Video]
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mouse from merced
Trad climber
The finger of fate, my friends, is fickle.
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Apr 29, 2015 - 11:26am PT
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