DiaStar Original

A scratched hardmetal case is a material finding

Hardmetal is very substantially harder than steel and does not scuff in ordinary wear. A case presented as hardmetal that carries the fine scratch haze normal on a worn steel watch is either steel, or plated, or has met an abrasive it should not have. The case can still be DENTED and can CHIP — hardmetal is hard and brittle rather than tough — so a chip at an edge is consistent with the material where a field of light scratches is not. That distinction is the whole check and it is easy to get backwards.

Weight is the second material check and needs no equipment

Tungsten carbide is roughly twice the density of steel. A hardmetal DiaStar is conspicuously heavy for its size, in a way that is immediately obvious in the hand against a steel watch of the same dimensions. A light case on a hardmetal claim is inconsistent, and the two checks — weight and scratch behaviour — corroborate each other from different directions.

Sapphire from 1962 is unusual and is part of the identification

The DiaStar was fitted with sapphire at a period when acrylic was standard. An early DiaStar with an acrylic crystal has been re-crystalled with the wrong material — a service finding, common enough, and one that also removes the scratch resistance the watch was sold for. Test by touch and thermal behaviour rather than by looking: sapphire feels cold and rings differently.

The anchor at twelve should swing freely

Rado's anchor emblem is mounted to rotate: on a genuine dial it swings under gravity as the watch is tilted. It is not printed and not fixed. Tilt the watch and watch it move. A static anchor — printed, glued or seized — is either a counterfeit dial or a damaged genuine one, and the two can be told apart by looking at whether there is a pivot at all.