Trothe Free ring sizer

Eight metals

Materials

Four numbers decide almost everything about living with a ring: how hard the surface is, how heavy it is, whether it can be resized and whether it carries a hallmark. Here they are side by side, including where each one loses.

MaterialHardnessDensity ResizeHallmark
Anodised zirconium
Colour made by voltage
Mohs 8.5 6.5 No n/a
Black zirconium
Black all the way through the surface
Mohs 8.5 6.5 No n/a
Titanium
The light one
Mohs 6 4.5 No n/a
Precious inlay
Real gold, contemporary price
Mohs 8.5 7.2 No Yes
Sterling silver
Hallmarked precious, at the lowest price
Mohs 2.75 10.5 Yes Yes
9ct gold
Precious, at half the metal cost
Mohs 3.5 11.2 Yes Yes
18ct gold
The traditional choice
Mohs 3 15.6 Yes Yes
Platinum 950
The heavy white metal
Mohs 4.5 21.4 Yes Yes
Palladium 950
White, hallmarked, lighter than platinum
Mohs 4.75 12 Yes Yes

Hardness is Mohs at the surface, which for zirconium means its oxide rather than the metal beneath. Density is g/cm³, and it is what people mean when they say a ring feels substantial. Not sure? The metal chooser asks six questions and gives you one answer.