the bedrock
quartzite
sugary fused grains · not vein quartz
The tell
Sandstone that has been cooked. It faintly sparkles, will not scratch with a steel knife, and when it breaks it breaks THROUGH the sand grains rather than around them.
This is the toughest common rock on a Great Lakes beach, which is why so much of what survives the trip is quartzite.
What it gets mistaken for
The facts
- also calledsandstone squeezed hard · breaks glassy
- age~2.3 to 1.7 billion yrs
- where it turns upevery shore · glacial float
- the field markgritty look, glassy break · snaps through the grains
10% of every order goes to northern Michigan animal shelters.