Are they both made of granite?
Stuart
Yes... Well as best as I can tell.
hmmm... After doing some digging on the stickered manufacturers I'm even more confused than I originally was. The bottom plate has a "rock of ages" badge which means it was born in Vermont. The top plate being a "Collins micro-flat" comes out of California. My confusion lies in a google search to confirm the composition of the Collins for stupoty.
A vast majority the images for the Collins have it shown with an undersized plinth of the same material, which I'll admit isn't something I'm used to seeing a surface plate with. At any rate, I'm now wondering if someone just got bored and for gags stuck these Rock of Ages badges on the plinth.
extropic: The thread is about breaking down a silicone bond between what I believe to be separate surface plates. Before and after the posted pic I have written a few sentences describing the joint between the two plates. The pic was included so the joint/bond under discussion could be visually referenced. I'm unsure how the physical orientation of the plates or the size of them effects the chemical composition of silicone or epoxy, but here's what extra I can offer at the moment. The "top" plate (aka: the one I care about) is 36x24x~3". The bottom plate, lets call it "the plinth" for now is a few inches smaller than 36, a few inches smaller than 24, and I'd hazard to say pretty close to 3" thick. If you need accuracy beyond that it will have to wait till later this morning. It's cold out, I'm enjoying the Sunday morning with family and it's going to take more than a need of inconsequential dimensions to get me to brave that cold at the moment...lol.
Here's a pic of the lot listing if you think it will help.
If you're interested in getting a closer look of what bond between the plates looks like, please reference the first pic I posted.
For what it's worth.. The badging on the "top" and "plinth" follow what you'll see after a google images search of the manufacturers spoken of earlier. My point..., neither of the badges were written in Sharpie so I believe them to be authentic on some level.