Pumpellyite/Greenstone?

[Capt Nemo]

Found a pair of these within a foot of each other east of Grand Maris, MI. I haven't seen any more on the beach.

Streak is white. If this is greenstone, it's a big one, as most are the size of a dime.

 

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[Eu_citzen]

Gabbro.

 

[hvacker]

Looks like a pudding stone to me. They're a conglomerate and can be of different minerals.
There's even a pudding stone festival somewhere in Michigan.

 

[justbrian55]

Looks like a pudding stone to me. They're a conglomerate and can be of different minerals.
There's even a pudding stone festival somewhere in Michigan.

There ya go. Nemo prolly wanted a good reason to take a ferry ride.

 

[Capt Nemo]

Here's a polished greenstone.



Highly doubt puddingstone, as it's the wrong color for it in the area found. Some of the black areas act like feldspar in the light.

 

[Eu_citzen]

The black areas are pyroxene, and can act like feldspar. Gabbro, for sure.