To fully understand why soapstone feels so special to the touch, we have to dig a little bit, exploring how our fingertips detect texture, and the composition of soapstone.
You know that squeaking sound you hear when you rub your fingers across a “squeaky clean” window? It’s generated by the vibration of the skin on your finger when you rub the surface. Receptors under the skin’s top layer detect these vibrations, which we then interpret as different types of surfaces (“oh, that’s a sticky surface,” or “that feels like glass,” etc.).
Our fingertips are extraordinarily sensitive to vibration, even ones we cannot hear. This is due to receptors called Pacinian corpuscles, small vibration receptors located just under the skin.
Fingertip sensitivity to minute vibration lets us “feel” textures even without looking at them. For example, if your fingers glide on a surface covered in wet soap, the fingertip will be in a viscous liquid and therefore doesn’t vibrate, signaling a message for your brain: “ooooh, this feels smooth.”
The reason our fingertips don’t stick to soapstone is that there are talc crystals inside the matrix of the stone. Talc is characterized by a pronounced soapy feel, with a pearly luster and softness. These crystals are a very special neutrally-charged layered mineral that does not stick to fingertips.
When you caress soapstone, the tip of your fingers will slide on the surface without detecting vibration. You might say it “feels soapy.”
And this is how soapstone got its name.