[ home / board list / faq / random / create / bans / search / manage / irc ] [ ]

/rocks/ - Rocks minerals and fossils

Your board for your favorite rocks, minerals and fossils

Catalog

Name
Email
Subject
Comment *
File *
* = required field[▶ Show post options & limits]
Confused? See the FAQ.
Options
Password (For file and post deletion.)

Allowed file types:jpg, jpeg, gif, png, webm, mp4
Max filesize is 8 MB.
Max image dimensions are 10000 x 10000.
You may upload 5 per post.


File: 1411441832324.jpg (1.63 MB, 2970x1980, 3:2, rocks-from-Grand-Marais-ha….jpg)

 No.56[Reply]

I'd just like to say to Admin that this board is sitting-by-the-fire-tier /comfy/

Anywho, post here for identification in case you have any on hand you aren't sure its species.
17 posts and 10 image replies omitted. Click reply to view.

 No.334

>>332
Perhaps just an amphibian board, or a board for reptiles and amphibians?

 No.335

File: 1417847127615.jpg (166.16 KB, 640x480, 4:3, flower_octapus.jpg)

>>334
That sounds cool although I don't know much about reptiles and such. I was also considering making a flower board.

 No.340


 No.756

File: 1431722867990-0.jpg (211.16 KB, 1280x960, 4:3, IMG681.jpg)

File: 1431722867991-1.jpg (260.1 KB, 1280x960, 4:3, IMG683.jpg)

File: 1431722867991-2.jpg (230.07 KB, 1280x960, 4:3, IMG682.jpg)

Help with these please? I'm only interested in the biggest two, and maybe the dolomite/marble one, really.

If it helps, those were picked up in Quabbin Reservoir, MA.


 No.763

File: 1432446249023.gif (7.04 KB, 375x423, 125:141, QAPF.GIF)

>>756

Pic 1:

Marble is comprised of calcite crystals +/- any impurities. Since it's nearly momomineralic, it'll share many of the same properties as the crystal: if you put an acid like lemon juice or vinegar on it, it should vigorously effervesce. If it's dolomitic marble, it will only fizz weakly and only if powdered.

2 on the right in the 2nd row might be feldspars but hard to tell in your pic

"granite" in the upper left is unlikely to be a granite. I'd guess it's probably going to plot as something like a quartz monzonite or quartz monzodiorite. Could be it's a true granite but I'm guessing it's not.

Pic #2:

That's a chunk of gneiss. You've got a biotite-rich top and a quartzofeldspathic bottom. Probably formed from a sedimentary protolith based on how much aluminum that's probably got in it and at somewhere around 600-800 C

Pic 3:

That's more likely a chunk of pegmatitic quartz. Do the acid test from pic 1 and check the hardness - quartz is harder than steel, calcite/dolomite are not. The shiny bits in there look like muscovite.




File: 1431222912784.jpg (259.06 KB, 910x709, 910:709, 1431152357180.jpg)

 No.751[Reply]

are there pink rocks?

 No.758

File: 1432065867814.jpg (41.25 KB, 1400x1050, 4:3, Halite2101B.jpg)

Feldspar, quartz, cinnabar, halite, many others.

Examples: http://geology.about.com/od/mineral_ident/tp/Red-Pink-Minerals.htm


 No.761

File: 1432347404180.jpg (56.72 KB, 700x490, 10:7, crystal_guide_crystalitas_….jpg)

Rose quartz is the one you most commonly see.


 No.762

>>761

Maybe in gift shops

>>751

In nature manganese minerals are commonly pink such as rhodonite or piemontite




File: 1432184738248.jpg (106.92 KB, 1366x768, 683:384, FinestarDiamond.jpg)

 No.759[Reply]

Anyone here with knowledge about good opportunities in the gem - jewelry industries? From being a cutter, faceter, appraiser, etc.?



File: 1424911385995.jpg (787.45 KB, 850x729, 850:729, 0001038001336495175.jpg)

 No.540[Reply]

Chalcedony thread.
41 posts and 83 image replies omitted. Click reply to view.

 No.742

File: 1430170645260-0.jpg (270.79 KB, 1024x682, 512:341, 0744231001400424306.jpg)

File: 1430170645261-1.jpg (96.33 KB, 682x1024, 341:512, 0745733001397328169.jpg)


 No.743

File: 1430170663625-0.jpg (277.81 KB, 682x1024, 341:512, 0748330001399241300.jpg)

File: 1430170663626-1.jpg (166.97 KB, 1024x682, 512:341, 0803415001381227217.jpg)


 No.744

File: 1430170690221-0.jpg (91.31 KB, 1024x682, 512:341, 0814995001397329797.jpg)

File: 1430170690222-1.jpg (94.93 KB, 1024x682, 512:341, 0834018001397329622.jpg)


 No.745

File: 1430170725036-0.jpg (384.52 KB, 1024x697, 1024:697, 0866863001399233373.jpg)

File: 1430170725037-1.jpg (224.1 KB, 1024x682, 512:341, 0893839001397472775.jpg)


 No.746

File: 1430170775410-0.jpg (109.61 KB, 1024x682, 512:341, 0905403001400457588.jpg)

File: 1430170775410-1.jpg (176.57 KB, 1024x682, 512:341, 0953709001397396065.jpg)




File: 1428241710293.png (1.03 MB, 931x969, 49:51, peter-cottontail.png)

 No.681[Reply]

Here comes Peter Cottontail
Hoppin' down the bunny trail
Hippity hop hop Easter's on it's way

Happy Easter geophiles

 No.723

>>681

thank you peter cotton tail happy easter friend




File: 1424804948004.jpg (73.53 KB, 800x538, 400:269, crystals7.jpg)

 No.524[Reply]

This is a crystal cave in Mexico. Are they very rare? Where else in the world does this exist? Are they ever colorful?

How would one come across seeing the beautiful colorful rock formations in real life? Are they usually clustered together or spaced widely apart?
4 posts and 1 image reply omitted. Click reply to view.

 No.619

>>608
I'd love to watch if someone can name this doc

 No.623

Remember that these crystals only form in water.
So even if they did exist, the cavity would need to be drained really recently to have anything remain

 No.676


 No.679

>>676
thank you lovely anon

 No.680

>>676
I gotta get around to watching this.



File: 1411219954530.jpg (55.73 KB, 500x333, 500:333, 1320-500.jpg)

 No.2[Reply]

Best rock
4 posts and 2 image replies omitted. Click reply to view.

 No.21

File: 1411279247120.jpg (75.55 KB, 703x427, 703:427, 31350-1qc2wuq.jpg)

>>12
This. They're on the same level as diamonds. Quartz is much better.

 No.22

File: 1411281475693.jpg (26.32 KB, 432x432, 1:1, 19089.jpg)

Thoughts on tanzanite?

 No.24

File: 1411284357383.jpg (56.68 KB, 565x750, 113:150, TAN07-Natural-Tanzanite-Cr….jpg)

>>22
I love tanzanite. I've been meaning to add some to my collection but I won't have the chance to until October.

 No.661

hows it going?

 No.677

File: 1427742041196.jpg (95.97 KB, 500x485, 100:97, basalt_massive.jpg)

Basalt



File: 1426991180930-0.jpg (2.16 KB, 82x93, 82:93, eelem.jpg)

File: 1426991180930-1.gif (1.64 KB, 48x100, 12:25, earthelemental.gif)

File: 1426991180930-2.gif (1.92 KB, 47x100, 47:100, magmaelemental.gif)

File: 1426991180930-3.gif (12.6 KB, 99x131, 99:131, mineral.gif)

 No.664[Reply]

Does rocks approve of Earth Elementals?

In WoG NU you can upgrade them to Mineral Elementals

 No.665

File: 1426991437531-0.gif (16.66 KB, 270x256, 135:128, earth.gif)

File: 1426991437531-1.jpg (15.51 KB, 156x205, 156:205, zz.jpg)

File: 1426991437531-2.gif (25.86 KB, 289x250, 289:250, earth_elemental.gif)

File: 1426991437531-3.jpg (68.16 KB, 600x600, 1:1, art_earth_elemental.jpg)


 No.666

File: 1426991664445-0.jpg (2.27 KB, 82x93, 82:93, igolem.jpg)

File: 1426991664445-1.jpg (2.37 KB, 82x93, 82:93, sgolem.jpg)

File: 1426991664445-2.gif (2.55 KB, 36x80, 9:20, Creature_Stone_Golem.gif)

File: 1426991664445-3.gif (2.86 KB, 40x84, 10:21, Creature_Iron_Golem.gif)

Or Golems?

 No.668

File: 1426991947696-0.gif (2.86 KB, 37x91, 37:91, Creature_Gold_Golem.gif)

File: 1426991947696-1.jpg (6.89 KB, 100x130, 10:13, diamondgolem.jpg)

File: 1426991947696-2.jpg (13.53 KB, 140x210, 2:3, golem.jpg)

File: 1426991947696-3.gif (3.36 KB, 90x117, 10:13, crystaldragon.gif)


 No.669

File: 1426992221387-0.gif (17 KB, 226x250, 113:125, crystal_guard.gif)

File: 1426992221387-1.gif (24.48 KB, 269x250, 269:250, crystal_dragon.gif)

File: 1426992221387-2.jpg (32.5 KB, 600x600, 1:1, art_gold_golem.jpg)

>>668
Let's not forget Escaton's servants

 No.674

I've always liked golems and other rock monsters in video games.



File: 1425154039673.jpg (17.29 KB, 220x240, 11:12, unicorn.jpg)

 No.579[Reply]

What does /rocks/ think of crystal healing and the magical properties of rocks?
4 posts omitted. Click reply to view.

 No.609

I don't know about healing or magic, but you can definitely feel how quartz crystals affect your energy field if you hold them. I don't think I've gotten that from other crystals, but with quartz it is noticeable.

 No.610

>>609
I hope you die in a meth-related cooking accident

 No.624

>>610
>hating on the Chakra-aligning power of quartz

Get out of here black pill

 No.635

>>579
sage

it's shit

 No.654

>>579
LOL SHE A DICK HEAD



File: 1426116636839.jpg (45.47 KB, 550x365, 110:73, flat,550x550,075,f.jpg)

 No.626[Reply]

Is it legal to own a stalagtite?
Also stalagtite and stalagmite thread.

 No.630

>Buy land on karst topography
>discover cavern on property

Yes

 No.631

File: 1426356794448.gif (1.72 MB, 318x242, 159:121, Consider the following.gif)

>Is it legal to own a stalactite

If you took it off the ceiling or floor how would you prove that it was a stalactite or a stalagmite?

 No.632

>>631
It's still a rock from a cave!

 No.634

File: 1426529884883.png (19.46 KB, 522x639, 58:71, Untitled.png)

>>631
Wouldn't the drip pattern make it obvious? Stalagmites tend to be a bit broader since the carbonic acid could rest on top of the existing stalagmite with gravity pulling it off-center to the sides. Whereas on a stalactite the acid would be pulled inward towards the center as it drips down



File: 1424811220513.jpg (52.49 KB, 581x403, 581:403, Mitchell-Hedges-Skull.jpg)

 No.532[Reply]

So what does /rocks/ think about the crystal skulls? Are any of them not hoaxes?

 No.625

I think they're fake.NEXT

 No.633

I've never heard anything about crystal skulls but if people assume that they're anything like that movie then they are sorely mistaken.



File: 1425933734524.jpg (70.4 KB, 960x539, 960:539, 11034243_828141597259308_4….jpg)

 No.614[Reply]

This is what I do in my spare time. Clockwise starting at the top left:

Basalt (igneous, aphenitic, mafic, and probably plutonic judging by the lack of vesicles).

Obsidian (igneous, aphenitic and amorphous, felsic, volcanic).

Dioritic Pumice (Igneous, phaneritic, felsic, volcanic). Evidence of a very volatile stratovolcano probably formed inland from a subduction zone. It's delicate too, I had to but it in a plastic box because it sheds pyroclastic material (volcanic "ash") if handled too roughly.

Vesicular basalt (igneous, porphyritic [otherwise aphenitic with phenocrysts], mafic, volcanic). I'm not sure what exactly is in the phenocrysts, but its likely to be high in silica and perhaps precipitated from the lava (mafic rocks tend to solidify at higher temperatures than felsic rocks due to silica's low melting point). I hypothesize the contracting basalt squeezed out impurities as it rapidly cooled after the lava surfaced.

 No.615

You sound like you've heard a bunch of jargon but don't actually have much of an idea of what you're talking about.

Such as
>>Basalt, high in silica

 No.616

File: 1425936423237.png (79.35 KB, 1370x472, 685:236, Untitled.png)

>>615
I said the phenocrysts were high in silica, not the matrix (basalt itself).

And the phenocrysts are likely to have concentrated levels of silica. Mafic rocks with low silica content undergo a phase change at higher temperature (and are generally denser than felsic rocks anyways)

So if the lava is extruded, and experiences a drastic loss of heat, then the basalt itself would would solidify before floating bits of felsic mineral would. The solidification of the basalt would only make it denser, and the low density felsic minerals would be expelled, possible into the vesicles

 No.617

File: 1426002553395.jpg (33.31 KB, 696x519, 232:173, GEOTHERM3.JPG)

>>Mafic rocks with low silica content undergo a phase change at higher temperature

A phase change to what? Do you mean they melt when they're heated?

>>the basalt itself would would solidify before floating bits of felsic mineral would.

No, your phenocrysts already crystallized prior to eruption. Also:
>>What is viscosity?

I'm sorry but but only have the vaguest idea of what you're talking about

 No.618

>>615
>>617
are we being pedantic on a dead board now? is that fun for you? if you know stuff about rocks contribute a thread with some information instead of rudely pissing on other people's.. just a thought
I like OP's post, thanks OP, cool rocks

 No.629

>>617
>A phase change to what? Do you mean they melt when they're heated?

Exactly. They have a higher melting point. Granted this will increase with pressure, but generally, when magma rises through the earth and cools, metal rich minerals will tend to solidify first

>No, your phenocrysts already crystallized prior to eruption.


No, they wouldn't. most silica-rich rocks would still be liquid if they were encased in molten basalt. They would be the LAST thing to solidify



File: 1424805648245.jpg (535.45 KB, 801x525, 267:175, Mar-Chiquita.jpg)

 No.526[Reply]

it's very nice

 No.527

File: 1424805662101.jpg (114.24 KB, 800x600, 4:3, marchiquita-5.jpg)


 No.528

File: 1424805687186.jpg (43.74 KB, 584x438, 4:3, marchiquita-bom-04-2012-58….jpg)


 No.620

File: 1426070844425-0.jpg (107.09 KB, 1024x576, 16:9, 0092510001378880914.jpg)

File: 1426070844425-1.jpg (168.62 KB, 1024x768, 4:3, 0755948001247811107.jpg)

Here are some from Spain.

 No.621

File: 1426070894936-0.jpg (114.13 KB, 1024x577, 1024:577, 0690878001402299804.jpg)

File: 1426070894936-1.jpg (255.59 KB, 1024x768, 4:3, 0715643001378902460.jpg)

Italy

 No.622

File: 1426070920713-0.jpg (111.44 KB, 1024x768, 4:3, 0590589001378280306.jpg)

File: 1426070920713-1.jpg (136.71 KB, 1024x768, 4:3, 0728219001378223120.jpg)

File: 1426070920713-2.jpg (279.7 KB, 1024x768, 4:3, 0796096001247835374.jpg)

Arizona



File: 1411324800325.jpg (68.54 KB, 600x450, 4:3, sandstone.jpg)

 No.37[Reply]

Post close-ups only.
15 posts and 25 image replies omitted. Click reply to view.

 No.498

File: 1423475439039-0.jpg (190.37 KB, 1024x722, 512:361, 0938966001413884838.jpg)

File: 1423475439039-1.jpg (117.29 KB, 1024x722, 512:361, 0963147001413893537.jpg)


 No.502

File: 1423678210591.jpg (25.69 KB, 240x172, 60:43, 3683335107_d2cc8e22e3_m.jpg)

>No onii-chan, that's too close!

 No.593

>>489
>>490
>>491
>>492
>>493
>>494
>>495

Are these all reflected light?

 No.612

>>593
Looks like a thin section under a polarized light microscope.

This sort of makes me miss the old days when I used to sit behind the petrographic microscope for 6 hours a day (not really).

Too much of this shit will ruin your vision.

 No.613

>>38
>>40
Are transmitted polarized light, >>593
All those are reflected light



File: 1411620772425.jpg (1.14 MB, 1592x1596, 398:399, Quartz,_Tibet.jpg)

 No.82[Reply]

I don't think I'm going to get much response on /geo/ so I'll just post this here.

I've been on the lookout for quartz of late but have had no luck. Any advice as to regions/locations I should be looking? Also what's the best way to harvest it?
>I'm from New England.
37 posts and 81 image replies omitted. Click reply to view.

 No.596

>>595
They're all quartz.

 No.601

>>596
Why do they all look so different in color/shape/size/opacity?

One of them is iridescent like bismuth. Rocks are confusing.

 No.602

>>601
I was just being a smartass. They are all quartz but there are a wide variety of quartz including:
amethyst >>416
smokey quartz >>98
and rainbow quartz like in the 3rd image here >>408

 No.603

>>601
Quartz commonly has impurities in it like Ti, Fe, Al etc which affect the color. Also microscopic fluid inclusions can give it a white translucent look.

 No.604

File: 1425623628471.jpg (32.51 KB, 461x394, 461:394, SilicaPhase.jpg)

>>603
Oh and temperature plays a role. Amethyst (purple quartz) becomes yellow quartz (citrine) upon heating.

As far as geologists are concerned, everything in this thread is alpha quartz. Silica can take a lot of different forms so not all SiO2 is quartz.



Delete Post [ ]
[]
[1] [2] [3] [4]
| Catalog
[ home / board list / faq / random / create / bans / search / manage / irc ] [ ]