Gold vs Pyrite
Gold and Pyrite are commonly confused, and 2 measured properties separate them — density most clearly.
Gold vs Pyrite
These are different kinds of thing (element, mineral). Fewer properties mean the same thing across both, so a like-for-like reading may not be available.
Pyrite
FeS2
Iron sulfide — fool's gold — a mineral more valuable for the sulfur it yields and the acid it produces than for the iron in it.
| Property | Gold | Pyrite |
|---|---|---|
| Atomic number Only one of the two has a figure we can stand behind, so there is nothing to compare. | 79 | Not known |
| Cleavage Only one of the two has a figure we can stand behind, so there is nothing to compare. | Not known | indistinct; fractures conchoidally |
| Crystal system Only one of the two has a figure we can stand behind, so there is nothing to compare. | Not known | cubic |
| Density | 19.32 g/cm³ higher | 4.95–5.1 g/cm³ |
| Electrical conductivity Only one of the two has a figure we can stand behind, so there is nothing to compare. | 45.2 MS/m | Not known |
| Lustre Only one of the two has a figure we can stand behind, so there is nothing to compare. | Not known | metallic |
| Melting point Only one of the two has a figure we can stand behind, so there is nothing to compare. | 1064.18 °C | Not known |
| Mohs hardness Mohs hardness is an ordinal scale: values can be ranked, but differences and ratios between them are not meaningful. | about 2.5 | 6–6.5 higher |
| Molar mass Only one of the two has a figure we can stand behind, so there is nothing to compare. | 196.96657 g/mol | Not known |
| Streak Only one of the two has a figure we can stand behind, so there is nothing to compare. | Not known | greenish-black to brownish-black |
Why these get confused
the resemblance is superficial — pyrite is hard and brittle where gold is soft and malleable
The confusion is a real and documented one, not a resemblance we have invented.