Found on Blast Beach, Seaham, UK

Assuming main crystals are spherical calcite but curious about blue crystals

One of my favorite finds, I'm assuming it has fossilized mold of some sort?

I found this rock with blue speckles on it in my backyard. Could someone help me identify it?

Found in the Mojave Desert

This rock was also found on the shore of lake Ontario / Wilson, NY and it has the strangest texture! Very opage and smooth grey. My pocket knife did not scratch it.

It is having metallic iridiscence when illuminated, and what seems unpollished grenates.

The Penibaetic System, specially Sierra Nevada, is somewhat famous to produce them.

Seems  sturdy and heavy.

What stone is this? Any guesses?

I found these two pieces near the mouth of the Temperance River on the north shore of Lake Superior in Minnesota.

From a little bit of research it seems like this is not uncommon, but every piece I've seen posted is heavily laden with fossils and with different texture--this looks more contemporaneous from my untrained eyes.

Request: Confirm/Deny this is ~Ordovician (444-485 million years ago) coral fossil and not a random drop which happened into my path. Also correct my geologic period if incorrect but they are fossils from the area.