Building materials — what they are made of

7 building materials objects, broken down.

Object	Made of
Glass	Sand melted with soda ash and limestone — three cheap minerals, floated flat on molten tin.
Concrete	Stone and sand glued by cement paste — and it hardens by a chemical reaction with water, not by drying.
MDF	Wood pulled apart into individual fibres, mixed with resin and wax, and pressed hot into a board.
Road asphalt	About 95% crushed stone and sand, glued together by roughly 5% bitumen from the bottom of an oil refinery.
Brick	Clay and shale moulded and fired until the particles partly fuse — a manufactured rock.
Mirror	A sheet of ordinary glass with a microscopically thin silver layer on the back, sealed under paint.
Plywood	Thin wood veneers glued in alternating grain directions — the cross-lamination is the entire idea.

Glass Sand melted with soda ash and limestone — three cheap minerals, floated flat on molten tin.
Concrete Stone and sand glued by cement paste — and it hardens by a chemical reaction with water, not by drying.
MDF Wood pulled apart into individual fibres, mixed with resin and wax, and pressed hot into a board.
Road asphalt About 95% crushed stone and sand, glued together by roughly 5% bitumen from the bottom of an oil refinery.
Brick Clay and shale moulded and fired until the particles partly fuse — a manufactured rock.
Mirror A sheet of ordinary glass with a microscopically thin silver layer on the back, sealed under paint.
Plywood Thin wood veneers glued in alternating grain directions — the cross-lamination is the entire idea.