


Here is an example of granodiorite, a rock with a slightly different composition from granite and it was quarried in Quincey, MA. The dark color is due to minerals such as dark gray feldspar and ferromagnesian minerals. It originated as magma and is more than 320 million years old.

This is another sandstone called Berea and it was obtained from Deep Lock Quarry in Peninsula. In it can be seen pebbles and clayey clasts.

The marble used to carve this piece is the same type used by Michelangelo to sculpt his Pieta and David. Called Carrara marble, it was quarried in the Italian Apuan Alps. According to the handy guide booklet, we find that this marble was the "result of metamorphism of a pre-existing limestone during the Jurassic Period, between 200 and 145 million years ago."

The oldest rock on our tour comes from Canada. It has a commercial name of Caledonia granite and is a billion years old. Contemplating it, I immediately felt like an insignificantly temporary collection of cells in comparison.

This beautiful floor pattern was created out of pink limestone from the Holston Formation of eastern Tennessee and the black limestone came from either New York or Vermont, Both stones originated as sea sediment in the Ordovician age and are over 400 million years old.


I really perked up my ears when I heard we would be seeing cephalopods in the next batch of rocks. Thanks to my favorite science blog, Pharyngula, I've become enamored of these beautiful creatures. Look closely and you will find fossils of large conical cephalopod shells in this gorgeous gray and pink limestone.
Come back tomorrow, and I'll post pictures of the actual sites where the above rocks and stones can be found.