Cast – A continuous cast aluminium plate machined on both sides to about 25 microinch finish and thermally stress relieved. This has the best thickness tolerance of any aluminium plate and maximum stability. Perfect for precision applications such as electronic base or mounting plates, photo vacuum plates, checking fixtures. Has good welding, anodising and corrosion resistance properties. No forming. Typically used in the 6 mm to 30 mm thickness range, but also available up to 150 mm.

Rolled – Aluminium alloy plate, usually in a 5000 series alloy, which has been rolled in the normal way. The aluminium plate is then super annealed to provide stability, after which it is precision face machined to provide close tolerance dimensions. This process is often carried out by processors as well as producing mills, and has a variety of trade or brand names that are often similar or equivalent to each other. This has some advantages over cast plate aluminium in welding or anodising, but may be less stable.