This rock was found in Lake/Lac Clair near Sturgeon Falls Ontario Canada in about 2 feet of water next to the edge of the lake. It can easily fit in my hand. You can see a size comparison in the first picture with the rock next to a Canadian quarter.

There is a fair amount of metallic sparkle when you hold the rock in the light. The bumps on the rock shine a little brighter than the rest of the surface. The rock is not very heavy and actually feels a little lighter than expected. The surface flakes a little but it doesn't leave residue on your hands.

I assume the slight brown colouration on one side is film from the lake floor but it doesn't rub off. The colour in the photograph is pretty accurate.

Thank you in advance for any information that helps identify this rock.

Rock size comparison enter image description here


Your rock appears to a metamorphic rock called a gneiss.

The regional regional of the area can be found here. enter image description here enter image description here

  • $\begingroup$ I am not convinced this is Gneiss, I would have expected some layering or at least some deformation of the phenocrysts along the plane of force. It is difficult without a higher magnification photo to see what the other crystals are doing. $\endgroup$ – Friddy Nov 5 '18 at 19:50
  • $\begingroup$ It looks more like schist than gneiss, but it is hard to tell without seeing it in an outcrop. Not sure what the large crystals (phenocrists) are. $\endgroup$ – haresfur Dec 5 '18 at 22:41

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.