Hey all, I came across this rock in a river in Western New York. There are two different parts of this rock.
There are smooth, rounded parts that are brown to red in color. Their is a slight luster or sheen to these parts and are also magnetic. There seems to be very defined line where this rock meets the other - but the two types are well fused.
The other parts of the rock are very porous and covered in pits. Black in color, with small chunksof white here and there (no more than a few millimeters wise with the largest being maybe 5 to six millimeters. These parts range from matte to glass-like luster. Parts of the these regions of the rock are softer, while others in the more glass like sheen are significantly harder. I was able to completely remove a solid chunk of of the matte porous area and it left a clearly defined crater of significantly more sturdy rock. (Photo below)
It’d be great to hear some opinions on this.