Chalcopyrite vs Malachite
Chalcopyrite and Malachite are genuine alternatives to one another — a choice somebody actually makes — and differ on 4 measured properties, crystal system most clearly.
Chalcopyrite vs Malachite
Malachite
Cu2(CO3)(OH)2
A green copper carbonate — an ore, the oldest green pigment, and a banded ornamental stone, all from the same weathered copper deposit.
| Property | Chalcopyrite | Malachite |
|---|---|---|
| Crystal system Categorical values can be listed side by side but not ordered or subtracted. | tetragonal | monoclinic |
| Density | 4.1–4.3 g/cm³ higher | 3.6–4.05 g/cm³ |
| Lustre Categorical values can be listed side by side but not ordered or subtracted. | metallic | silky to dull, adamantine in crystals |
| Mohs hardness Mohs hardness is an ordinal scale: values can be ranked, but differences and ratios between them are not meaningful. | 3.5–4 | 3.5–4 |
| Streak Categorical values can be listed side by side but not ordered or subtracted. | greenish black | pale green |
Choosing between them
Malachite is recorded as a substitute for Chalcopyrite — cheaper, lower environmental impact.
What it gives up: Only present in the weathered cap, which is a small and finite part of a deposit.
In this application, on the evidence cited above.