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[R.U. Sirius]

After more than a few rocks have gone through my hands, I started paying attention to all sorts of non-visual clues, from density to surface quality under fingertips, to how it sticks to my bottom lip, to what's been intriguing me more and more: the sound.

Jade and petrified wood produce distinct ringing sounds when held and struck just right, and then there is the raspy, dry cardboard sound of rhyolites as we run our fingers across - suggesting porosity. I've heard prospectors talk about the sounds of their tools hitting the veins of this or that material.

Then of course there is the sound as we touch the rock onto the grinding wheel, and how it changes with pressure and throughout the process.

It'd be interesting to have experienced rockhounds chime in on the topic.

[lithicbeads]

I've hit many hundreds of rocks with a sledge and the one type that beat all others was a diabase from a mountain in Washington. Every boulder rang like a bell.

[irockhound]

Haha like the pun  lol chime in.  Another rock that has a distinctive sound is durmorierite.  You you drop a piece it sounds almost like metal.

[R.U. Sirius]

I've hit many hundreds of rocks with a sledge and the one type that beat all others was a diabase from a mountain in Washington. Every boulder rang like a bell.

Interesting! As far as the U.S. sites, the Wikipedia article on ringing rocks only lists several diabase boulder fields in Pennsylvania and one in Montana - your example from Washington may not be widely known, if at all.

[lithicbeads]

The one here is on Jumbo mountain which is extremely avalanche swept in winter. The boulder fields down low get replaced most winters with new rock. One year a forest fragment was torn loose from the mountain and it ended up on the bottom of the mountain sitting on 20 feet of snow that skidded down the mountain on. The dirt insulated most of the snow and it took two years for the snow to melt and the forest above to fall apart.On the other side of the mountain a few hundred acre landslide buried an old growth forest on the valley bottom 15 years ago and already oil is seeping out of the debris.

[R.U. Sirius]

The one here is on Jumbo mountain which is extremely avalanche swept in winter. The boulder fields down low get replaced most winters with new rock.

It's amazing how fast geological processes can be. We think about geological timeline in terms of millions of years, and tend to forget that an event may have taken place a long time ago, but may have been relatively fast - an eruption, flooding, earthquakes, even climate changes and geochemical processes can be relatively fast. A piece of petrified wood may be 80 million years old, but the replacement by silica may have only taken a few decades or centuries to happen, followed by millions of years of quiet time (until another event may change the surrounding chemistry or mechanics, and lead to colour changes, dendritic inclusions, brecciation, etc.)

[Felicia]

Saw a couple of programs where archaeologists found rocks, about 3' - 4' size, that had  areas that had been hit repeatedly (probably with other rocks) that they believe we're used musically maybe.

[Kaljaia]

There's a kind of jasper out this way that rings. If you kick around in a scree pile you can find it by the sound. Next jasper vein over produces no ring at all. I'll go grab a few pieces one of these days and see if I can record it.