I know that despite being hard diamonds are very brittle. But just how brittle are they? Are they easier to crush than a regular stone you may find outside? Could you easily smash it with a hammer?
Btw. What adjective describes a material that is not brittle yet very hard to deform (as opposed to for example a steel which is very elastic yet it deforms significantly before returning to its shape).
yes its easy to crush, if you hit it right and cleave it along a plane.
The large diamonds found in rock are crushed up by the rock crushers during process.
They don’t mind as the large diamonds contain many flaw, and anyway they don’t mind ensuring the available diamonds are so numerous everyone can have one… if they pay the De Beers price. They don’t want the situation to be that “well, there are 10,000 diamonds worth buying, and they are too expensive, so I won’t buy any!”.
There’s various ways to describe the strength of a material
Hardness, toughness, compressive strength, tensile strength.
Daimonds are hard, but not strong otherwise
I think the question here is something along the lines of whether anybody has ever broken a large diamond set in a ring just by dropping it. Are they that brittle or fragile?
I’ve seen diamonds crunched by hitting them on a kitchen faucet. It can happen.
You can break a diamond just by dropping it onto a hard surface. They are fragile enough that it can happen, but not so fragile that it happens all the time.
Accidentally hitting your ring against the handle of a shopping cart is another common way for diamonds to be damaged. Whack a diamond with a hammer and you’ll easily shatter it.
The term that the OP is probably looking for is “toughness” or “tenacity”. This is a measure of how much the material can absorb energy while resisting shattering.
Other measurements are tensile strength, compressive strength, and sheer strength. Tensile is pulling it apart, compressive is squishing it together until it deforms or breaks, and sheer is applying a force to it so that part of it will slide against the rest (i.e. sideways).
Ductility is a material’s ability to deform while under tensile stress (example, pulling a piece of metal out into a wire). Malleability is the ability to deform while under compressive stress (example, hammering a piece of metal into a thin sheet).
Diamonds are pretty much at the top of the scale for hardness. Scratch a diamond against pretty much anything else and the other thing gets scratched and the diamond doesn’t. Diamond’s don’t do so well on all of the others though. Their crystal structure makes it very easy for them to sheer in certain directions (this is called cleavage). Because they are so hard, diamonds are difficult to “cut” in the normal sense. If you want to cut through a diamond you pretty much need another diamond to do it. Instead, jewelers will more often cleave a diamond along its natural cleavage planes instead of cutting them.
How would you compare a diamond’s fragility with that of more common minerals notorious for their tendency to cleave easily, like topaz, fluorite, or Iceland spar (calcite)?
Diamonds cleave and chip, but not as easily as topaz, fluorite, or calcite.
Suppose one could use some sort of nanotech manufacturing to make a window pane out of diamond. How would it compare in terms of durability to a glass window pane?
From answers above I figure it would be just as easy to break, but it would be extremely scratch resistant.
Also I bet it it possible event today to make large pane of diamond - they are making sapphire phone screens after all…
It is not, actually. Synthetic diamonds are nowhere near as easy to make as corundum. Well, a better way to say is that while corundum is easily grown in huge crystals, diamonds get much harder to make the larger you try to make them.
Synthetic diamonds are made either by chemical vapor deposition, or else the high-pressure, high-temperature process, which is about what it sounds like. It’s not hard to make very small diamonds this way, and in fact I believe lab-grown diamonds have pretty much taken over the industrial diamond market. You can grow gem-quality diamonds, and small ones tend to be cheaper than small natural stones, but not by a lot. The break-even point is around a carat: it gets harder and harder to make good, gem-quality stones in the lab the larger they are.