The main difference between a rock and stone really is what they are. A rock is stone material at the site, like bedrock and mountains. Essentially, rock is the raw form of stone, a large undiluted mass of natural minerals. As such, stone is a smaller piece of rock. There is also a word stonerock, which sort of between of the two, a large detached piece of rock but not small enough to be called a stone. Large boulders are essentially stonerocks.
As a material, stone is a very interesting one. On one hand stone is very strong and willing to bend under your will, but on the other hand stone is very easily broken and will shattered if not handled carefully. It is very natural, very warm and lives very much like wood does, but its pace is slower and more methodical. Comparing stone to wood seems to be natural, as most people are at least familiar with the softer material of the two.
Both stone and wood share their nature of having harder and stronger variants, where the softer ones get scratched and dented very easily and the harder ones feel like nothing can bite into them. For hardness, there exist a measurement system called the mohs scale of one to ten. Mohs one in hardness is soft and scratches easily. Talc is most often used example of it, as you can easily scratch it by your nail or with pretty much anything else. However, mohs two is far from being talc in hardness. This is because the scale is ordinal, and every step is about ten times harder than the last. PG Black, one of my personal favourites is mohs 5,8 in hardness. It can take some serious damage from being used as a cutting board and can withstand some beating before breaking apart. However hard wood may be, stone will always have a leverage above it in hardness. Stone axes that used silicon as the head were usually on the hardness scale of six to seven. Personal experience says that a stone of hardness of 4 or more is well enough to be used to cut skin and flesh. Having an axe of mohs 7 can be sharpened enough to cleave meat and bone.
As I mentioned, the stone lives much like wood. Much like with wood, it all depends on the stone how much it lives. The best and worst example of stone living is marble. As expensive and beautiful as marble is, it has a tendency to warp under the elements and acidic materials tend to both erode and colour its surface. There are government houses across the world that have white marble on their outer walls, and they’re all screwed on the long run, and at some point these marbles need to be replaced with new sets, which will live just as much. It is very interesting to see how much a simple stone tablet can warp within a year when it’s left outside. At worst, it will crack and fall apart where the mineral has its weak spots. Often these hairline crack, as I call them, are can be seen with a naked eye. They tell where the stone can be divided as well as where to it. Veins are different mineral density running through the material, and if the mineral is harder than the main stone, it’s called a bone. For example, soapstone is mohs one in hardness in general, but the bone soapstones have can easily have a hardness of three or higher. This makes working with the stone harder than usual, as one has to take care to work evenly with the whole area and not just on or off the bone.
Why am I telling all this? Stone is a very warm and natural material that is very long lasting. It requires high amount of work to get out from rock and requires unimaginable skill to be worked with. It’s beauty as a larger object like kitchen level is unparalleled and having a kitchen level made of eg. Amadeus is a sight to have. To some extent, it is also a statement of stature and position one has, but such a level will last through generations if well kept. It is well worth the price it fetches.
A modern designer barely gives any thought on stone, it would seem. We have all these new materials from plastics to composites and everything they’ve given out. Stone still exist around us everywhere despite being replaced with arguably better materials, because while it is a stubborn hard bitch it still calls us and shows that it can still be used in millions of different things. Unlike with these newfangled materials, stone still has it’s own natural colour and every single piece is unique, never replicated. Every product that is produced from a stone, even if from the same block from the same rock, every single piece of stone is unique in what it is. Injection moulded plastic is always the same, every single time. Same vast majority of metal and alloy products.
The main thing with stone, in the end, is that it is a natural material. It acts and feels like it, and to work on stone, either in making a product or baking on top of it, requires one to admit to its quirks and just go with it. It holds a certain charm of secrecy, and the only way of really taking all from a simple slate of rock on your table is to get to know it.