In the summer of 1960, right after graduation from high school, I was working as an assistant to the geologist of Pittsburgh Coal Company; his name was Jacque VonFeld. At one point in the summer Mr. VonFeld went to northern New Mexico to evaluate an oil shale prospect. When he returned, he gave me this rock, explaining that a rancher in New Mexico found the formation to be so attractive that he used it as a building stone for his fireplace. The very first fire he built in his new home took out the house! I like the color and feel of this rock, and of course the story behind it.
The banding of alternating light and dark (kerogen-rich) is very attractive. The rock is so that splinters of the dark material can be lit like a candle. The delicate layering reflects a depositional environment (lake) that was marked by very little energy in the form of waves or currents.
Age & Formation
Eocene kerogen-bearing shale/marl, ~50 Ma, from northern New Mexico.