Identity HelpTektite or Naturally tumbled Obsidian?
What makes these small stones I discovered in southern Oregon so unique is that they appear to be banded obsidian inside, yet they appear to be black and colorless from the outside and quite rounded with pitting.
I have termed them Eclipsestones, due to their opaque color, which becomes translucent when backlit.
Each piece is smooth in shape, yet has a 360° pitted surface, as though created in an explosive burst much like a tektite.
I am not aware of any known tektites from Southern Oregon, making these stones rare and mysterious.
Depending on what these stones have been through, it's very possible they can be pitted from being tumbled around in a stream. To me, they look like banded obsidian. 
Although obsidian looks black and opaque, it often appears translucent when backlit, especially if the piece is small. And, banding isn't that unusual in obsidian. I agree that the pitting and rounded shape could occur from stream abrasion. Also, I'm not aware of any tektite that show banding, but I could be wrong on that one. Banded tektites do exist, but the ones I've seen were quite opaque. These stones depicted here look like typical translucent obsidian pebbles.
