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Reader Submissions: My Igneous Rock

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Admit it, rocks are special. The best ones are not just pretty but intriguing, even beautiful. Admit it, you actually like some rocks. Show us one of your favorite igneous rocks. If you don't know what you have, please try posting your pictures in the Forum instead.

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Slag from Portugal

It is obvious the rock has been subjected to high temperature and shock so much so the outside of the rock has melted. A magnet sticks quite firmly to the rock. There are what appear to be many olivi…More

Pelitic Metachert, Not an Igneous Rock, from New York

This rock is smooth as glass to the touch, it's dark red with tiny gold speckles and transparent to a depth of 1/8 to 1/4 inch in places.It's round on the top and contours to your hand. The bottom is…More

Glacial Chromite(?) in Pennsylvania

I have never seen a rock like this before, it is a rare find in this area. It is vey rare to find an all black rock of this size. This rock is also very smooth and heavy for its size. Both rocks were…More

Japanese Pumice

I like the look of the three together because of the color and size differences, and love that you can't judge a rock by it's size. The large pumice weighs 2.3 oz, the orange scoria weighs 0.6 oz but…More

Basalt Near Pilot Rock, Oregon

Unlike most lava around here, these flows are very smooth and gentle, giving a pleasing appearance to the roadside and surrounding hills.They look like someone sanded the rough edges off without leav…More

Slag from Georgia

This rock is very uncommon for this area to my knowledge. I have lived here my whole life and have never found one until now. It has many vesicles and appears to be covered in glitter as it will spar…More

Basaltic Lava, Cornwall

Although there is nothing particularly pretty or significant about the appearance of this specimen, this rock forms the BEDROCK of the property in which I live, and the soil above being relatively sh…More

Pyroxenite from Northern California

This stone is solid crystals throughout and has a lot of sparkle off the crytals even though the stone is stream worn. The outline of crystals are somtimes perfect squares on the surface of the worn …More

Argentina Basalt

smooth surfacecleantype of crystallization!nice sound when knockedI have been traveling 20 years in my expedition vehicle and I have never seen such crystalshttp://www.panoramio.com/user/823582 kind …More

Exfoliating Basalt, Australia

Very unusual exfoliation. All weathering I have previously witnessed has, as would be expected, been from the extremities working towards the centre. The blocks in this wall, particularly along the t…More

Basalt Bombs from Central Oregon

This basalt was molten when it left it's source, a cone who's north face blew in the distant past (est 3 - 5 ma). It sloughed off material in flight (for about two-to-three kilometers) then hit earth…More

Granite Glacial Cobble, New York

I first picked this rock up because it looked igneous and of a good size. It wasn't until I washed it that I noticed the unusual features of the pink and white colors offset by the veins and black cr…More

Rhyolite Clast in Tuff

What I like is the flow banding and the parallel grooves on one of the partly covered sides of the rhyolite. I'm not sure what caused the parallel grooving. Also, although not observable without a ha…More

Brown Streaky Obsidian

While the core of the rock appears to be solid obsidian. The external coating has striations that take on the appearance of petrified wood.I was visiting Paso Robles, California and spent the day at …More

Sodalite Syenite, Brazil

The bright blue crystals of sodalite blew me away! When I first saw this piece, I thought it was a manufactured product because blue rocks are so rare in nature. I pulled out all of my rock reference…More

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