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Today I get a micro lens for my cell phone, so I took some pictures which provide more details about my favosites fossil rock than I posted in This graph shows the structure for Favosties, Image from Url. The follwing are my new photos.

Hello! Please help me find out if the arched bands showing up after polishing this metamorphic rock are just random artifacts of sedimentation or an indication for petrified wood? The material reacts to vinegar. I picked the stone in Romania, Harghita county. Thank you!

Heat and pressure? How much heat and pressure does it take to wrap volcanic ash in melted rock. Here is on i found next to what im cleaning. Here is a photo of the volcanic. Ash inside of the. Rock. Some of my photos are too big so I cannot post them.

This is not a fossil, but I imagine someone on here can tell me what type of rock it is. The Back Story You know me. I’ve always got a story. One summer when I was 11 we were traveling with my dad who was working for the National Forest planting trees where forest fires had decimated whole mountains in Colorado. My grandmother from Florida came and traveled with us for 2 weeks. She was my favorite grandmother and we were very close. We were kindred spirits. I rarely got to see her, but we had a strong connection. She was a die hard rockhound from Florida. Not many rocks there. So she was like a kid in a candy store and she’d go hog wild collecting rocks. She’d bring an extra suitcase just for the rocks. Anyway, one day we were traveling through Colorado and pulled over out in the country by a meadow by a river. The water was low and slow and the river was wide with lots of rocks in the bed. My grandmother and I took a walk in the river bed and collected a number of cool rocks. I normally picked rocks that could fit in my hand. I remember those rocks being so cool. They were black, very fine grained and smooth from being tumbled in the river. I called them snowflake rocks. 39 years later I have no clue where those rocks are now. But back in June my younger brother texted me a pic of a rock asking me what it was. Then he told me he was in Florida visiting a cousin who had a bunch of rocks from our grandmother. Our cousin was going to throw them away. When he told me they were my grandmother’s that day came back to memory. It was a sweet memory of my grandmother who had passed away 24 yrs ago. My brother asked me if I’d like this particular rock. He told me he’d brink it back to Arkansas and I could get it when I came to visit next. I visited in July. This is the rock. Does this particular type of rock have a name or is it lumped in with a group. It is very heavy and very hard (it’s a rock, what can I say?). I think the white rock is harder. The white inclusions are quite hard. The band at the bottom is a different material, which I believe is a form of chalcedony.

Greetings, My lying eyes are struggling with the unlikely chance that the forms in this rock are biological in origin. This looks like coral to me: I see rough impressions of corallites, polyp anatomy, septa, hexagonal and circular chambers, and signs of stacked chambers where masses are sheared perpendicular to the exterior surfaces. The average diameter of the corallite-like openings is ~.5 cm. Many are smaller. Some are up to 2 cm. Note the manner in which various tilted tubes erode to reveal their lengths and interiors; and the presence of angle-cornered walls that group fields of corallite-like forms (LooksLikeCoral1.jpg). The bed from which these blocks and boulders emerged is sandwiched between crystalline limestone, garnet gneiss, and quartzite. These in turn are closely adjacent to a granitic intrusion. The rock shown here is metamorphic. It feels more dense than quartz, and seems at least as hard as quartz, and reacts very weakly with acid. At a broken edge, its separately fractured crystals reveals the nearly transparent vitreous luster, and the color is proportioned ~95% colorless and ~5% olive green. Examples of the most coherent masses of this rock are seen in LooksLikeCoral1.jpg and LooksLikeCoral2.jpg. A less coherent form of the rock includes a comparatively more easily eroded fibrous mineral that separates the tougher corallite-like layers (see LooksLikeCoral3.jpg). This fibrous mineral is composed of crystals which I believe have the same proportion of colorless and olive green. At the site of the rocks, there is a transition from coherent coral textured masses to less coherent: The fibrous fill increases in volume between ever more deeply curved layers of "remaining" hexagonal nuggets which gradually lose their walls. At one margin of the whole site, the fibrous filler is replaced with marble. And at another, where it approaches the granitic intrusion, there is a transition through stages of melt until the nugget layers are obliterated and mixed into a swirling fine grained mass, finally becoming indistinguishable from quartzite. The site is on privately owned land in the San Ysidro Mountain block of Eastern San Diego County, California. Quite some time ago, this block was determined to go back to the Ordovician, but no physical evidence for this claim has been found. I will test specific gravity, and next week, sections from a sample will be cut and polished for a look inside. I will share the results. In the meantime, it would be interesting to discuss: If you didn't know this was metamorphic rock, would you think these textures and patterns have biological origin? In the unlikely event this is fossil material, do the forms and patterns suggest an ID, and period? If you are forced to speculate that this could indeed be fossil material, what tough mineral/s might have first replaced the biological material so that it could survive the heat, pressure and deformation of mountain building? Just as interesting, can you suggest any non-biological processes that would result in forms and patterns like these? Thanks in advance for replies.