Granite under your amp???

T-6061 aluminum air hardens. By this time that amp stand must be like a trampoline-very lively. Not exactly what you may be looking for.

Granite (Harbor Freight has the machine plates on sale from time to time-free shipping also) is harder and more lively than marble. Granite is also a bear to work with without diamond tools.

18x18 inch marble tiles are usually available from a tile/carpet store. If you buy close-outs and partial boxes you can get it real cheap. 18x18 x 3/8 thick #3.00 USD per tile and free cutting to size if you ask nice (on a store wet saw a piece of cake). Again, marble has a low shear strength so it needs full support underneath at least on the amp contact points.

What Killerpiglet mentioned sounds interesting, it's very inexpensive.

I had an extra slab of 1" granite laying around from my kitchen so I did a little experiment... I placed it on top of my turntable stand with 4 Michell Engineering cones underneath it... and then my Gyro Dec on top... and it was the cheapest improvement in sound quality I have made in a long time...

Tim-When I had my audio crisis a couple of days ago I was considering taking a ride over the falls.David+99

I was able to get a couple of 15x24x1 polished scraps of marble from a local tile and counter shop for my amps. They had a pile of scraps from jobs and let me have them for free. All I had to do was clean them up.