How do you make chalk?

Question:

How do you make chalk?

how do you make chalk?

Best Answer - Chosen by Asker: "you must first create the universe" (-Carl Sagan)

Chalk comes from little things that live in the sea. Their shells sink to the bottom and stack up and stick together and migrate to land (sometimes). Then it becomes chalk cliffs and can be mined. It is called calcium carbonate and you might get some if you dissolve a sea shell in vinegar, then add some base or otherwise change the ph. Calcium carbonate.. .you mine it, grind it into powder, mix with a binding agent, mold into required shape, bake. Bingo. Chalk. I think it from a rock......maybe? You can make chalk from ground eggshell, flour and very hot water (food colouring too if you want to colour the chalk). It can take up to 3 days to set. Chalk used to write on black boards is Calcium Sulphate not Calcium barbonate.

TW K