Re: Black rock identification
Its very hard to tell from the photo, but in the upper corner it looks like it might have been chipped in a "conchoidal fracture", If so, and if it is as hard as quartz, I think you might have chert. Cherts and flints can look cubic or rectangular since they often form as flat layers between softer sedimentary rocks. I know nothing about the geology of the area but a quick googling confirms that chert is present in the rock formations composing the Olympic Peninsula. I hope this helps. Good luck.
From Adelaide Tenembaum - September 11, 2013 at 21:14:12