Xenotime vs Zircon
Xenotime and Zircon are commonly confused, and 3 measured properties separate them — density most clearly.
Xenotime vs Zircon
Xenotime
YPO4
Yttrium phosphate — the ore of yttrium and, unlike monazite, the mineral that concentrates the heavy rare earths.
Zircon
ZrSiO4
A tough silicate that traps uranium and refuses lead — which is how the age of the Earth is known, and the only real source of zirconium.
| Property | Xenotime | Zircon |
|---|---|---|
| Crystal system Categorical values can be listed side by side but not ordered or subtracted. | tetragonal | tetragonal |
| Density | 4.4–5.1 g/cm³ higher | 4.6–4.7 g/cm³ |
| Lustre Categorical values can be listed side by side but not ordered or subtracted. | vitreous to resinous | adamantine |
| Mohs hardness Mohs hardness is an ordinal scale: values can be ranked, but differences and ratios between them are not meaningful. | 4–5 | 7.5–8 higher |
| Refractive index Only one of the two has a figure we can stand behind, so there is nothing to compare. | Not known | 1.92–2.01 |
| Streak Categorical values can be listed side by side but not ordered or subtracted. | white | white |
Why these get confused
both tetragonal phosphate-like prisms in the same heavy mineral sands; zircon is harder and denser
The confusion is a real and documented one, not a resemblance we have invented.