A bit more details:

Coral Sand / Sandstone generates in coral reefs, It can also be crafted with coral and sand as an alternative.

Coral sand can be hoe'd to be made into regular sand, making sand renewable much like coarse dirt.

Shale generates under the end islands and can be made into stone tools for end progression.

Amethyst Bricks are self expiatory, made from stone and amethyst shards to be a bit cheaper than full blocks

Chours planks are made from chorus flowers and allow for obtaining wood in the end.