a block of something

3. N-COUNT : usu N of n

A block of a substance is a large rectangular piece of it.

• a block of ice.

8. N-COUNT : usu N of n

A block of something such as tickets or shares is a large quantity of them, especially when they are all sold at the same time and are in a particular sequence or order.

• Those booking a block of seats get them at reduced rates.

... Cobuild

cf. 3. A mold or form on which an item is shaped or displayed: a hat block. (Am-heritage)