These are pics from a strange rock formation on the summit of Turkey Mountain, Yorktown, NY. The lower parts of the hill have huge pieces of exposed bedrock made up of the typical fine-grained, grey-green, metamorphic rock. On the very top, there is this swirled, rough slab that to me looks like molten rock cooled. The quartz seems to be melted or folded into the dark swirled rock. The quartz also is very red in spots- there were areas of large fully formed crystals coming out of the quartz protrusions that someone has sinced harvested. The pictures dont really give you a macro feel for the location. the summit is allmost flat with this molten looking rock. There appears to be cracks from cooling. I dont believe this surface is due to weathering- the other gneiss does not weather like this- why would the protruding crystals not have weathered off. Volcanic features aren't normal to this area but there are intrusions of pegmatite and magnitite not far away. If I was out west, I would call this lava. Any thoughts- I'm no geologist.
BTW is a great easy hike with panoramic view of highlands with Manhattan skyline on a clear day
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