Used Rarely. rolling plan is in the lower 50% of commonly used words in the Collins dictionary
Most travertine is 3/8 of an inch thick but some other larger stones may be a 1/2 inch thick or more. 24x24 is usually 1/2 in thick an can even be as thick as 1in. 24in Travertine is extremely heavy , some pieces can weigh as much as 50 pounds. Thus making it very difficult to install and cut.
The unit of mass has been named the slug. The weight of a slug is about 32.17 lb. It is equal to 14.593 kg. Mass densities should be specified as slug/ft 3. Civil engineers adopted the slug, mechanical engineers didn't appreciate the problem, and chemical engineers did something else which I shall mention in a moment.