Is chrysocolla the same as malachite
No. Chrysocolla is a copper silicate, density 1.93 to 2.4; malachite a copper carbonate, density 4.05. They grow together; malachite weighs about twice as much.
No. Is chrysocolla malachite? Chrysocolla is a hydrated copper silicate, hardness about 2 to 4, density 1.93 to 2.4; malachite is a copper carbonate, hardness 3.5 to 4, density 4.05. They are separate IMA species that often grow together, and each Handbook sheet names the other. Same size, malachite weighs about twice as much.
In short
- Two species, two chemical classes. Chrysocolla is a silicate, (Cu,Al)2H2Si2O5(OH)4·nH2O on the Handbook sheet; malachite is a carbonate, Cu2(CO3)(OH)2. Both are copper minerals, often green, and both form where copper deposits oxidise.
- The same-size heft rule: malachite weighs 1.69 to 2.10 times as much as chrysocolla of the same size. Worked from the sheets' densities, a 2 cm cube is 15.44 to 19.20 g of chrysocolla and 32.40 g of malachite. A 20.00 g piece reads 9.64 to 11.67 g in water as chrysocolla and 15.06 g as malachite.
- Hardness does not separate them; streak and colour help. Chrysocolla's hardness reads ~2–4 on the rendered sheet and malachite's 3.5 to 4, so the ranges overlap. Chrysocolla's streak is white when pure and its colour blue, blue-green or green. Malachite's streak is pale green, and its sheet records it as commonly banded in masses.
- They grow together, so one piece can hold both. Chrysocolla's sheet names malachite first among its associates, and malachite's names chrysocolla. Twelve more of the 176 sheets in this site's reference set name both. The International Gem Society describes Eilat stone as a mix of chrysocolla, malachite and turquoise, at specific gravity 2.8 to 3.2.
- Chrysocolla prints the lowest density of any copper sheet in the set. Of the 43 sheets with copper in the formula, 41 print a measured density, and chrysocolla's lower bound, 1.93, is the lowest of them. Malachite's 4.05 is about twice its range.
| Criterion | Chrysocolla | Malachite | Does it choose? |
|---|---|---|---|
| Chemical class | Silicate | Carbonate | Yes, but by analysis |
| Formula, Handbook | (Cu,Al)2H2Si2O5(OH)4·nH2O | Cu2(CO3)(OH)2 | - |
| Formula, IMA list (Sept 2026) | (Cu2-xAlx)H2-xSi2O5(OH)4·nH2O; approved, 1980 s.p. | Cu2(CO3)(OH)2; grandfathered | - |
| Density, measured | 1.93 to 2.4 | 4.05 | Yes: about twice |
| Same 2 cm cube | 15.44 to 19.20 g | 32.40 g | Yes, in the hand |
| 20.00 g piece, weight in water | 9.64 to 11.67 g | 15.06 g; at least 14.44 g at the 3.6 floor | Yes: about 2.8 g apart |
| Streak | White when pure | Pale green | Yes, on pure material |
| Colour on the sheet | Blue, blue-green, or green; brown to black when impure | Bright green, dark green, blackish green; commonly banded in masses | Partly: blue points to chrysocolla, banding to malachite |
| Hardness (Mohs) | ~2–4 (rendered sheet) | 3.5 to 4 | No: they overlap |
| Lustre | Vitreous, porcelaneous, earthy | Adamantine to vitreous; silky if fibrous; dull to earthy if massive | No |
| Crystals | Acicular, to 5 mm | To 9 cm; typically botryoidal, radially fibrous inside | Rarely: both are usually massive |
| Copper by mass | 33.55% and 37.49% (the sheet's two analyses) | 57.48%, ideal | Only by analysis |
Is chrysocolla the same as malachite? The criteria, in the order that settles it
Chrysocolla and malachite are different minerals: one is a copper silicate, the other a copper carbonate, and their densities differ by about a factor of two. The Handbook of Mineralogy sheet for chrysocolla gives (Cu,Al)2H2Si2O5(OH)4·nH2O, crystal system Orthorhombic (?), and a density of 1.93 to 2.4. The Handbook of Mineralogy sheet for malachite gives Cu2(CO3)(OH)2, monoclinic, density 4.05. The September 2026 IMA list approves chrysocolla under the 1980 special procedure and lists malachite as grandfathered.
Weigh first, because density is the one criterion with no overlap. Then streak an unobtrusive spot: white for pure chrysocolla, pale green for malachite. Then look for banding, which malachite's colour line records. Hardness comes last and decides nothing: chrysocolla's sheet prints ~2–4, read from the rendered PDF because text extraction garbles the tilde, and malachite's is 3.5 to 4. The International Gem Society adds that chrysocolla can reach 7 when heavily silicified or included in quartz.
No acid test is given here. Malachite's acid sensitivity, and why this site does not recommend acid on a specimen, are on how to tell if malachite is real and why is my malachite dull. The identification pages are indexed at the collecting guides.
The same-size heft rule: a worked example
Malachite is 1.69 to 2.10 times as heavy as chrysocolla of the same size: 4.05 divided by 2.4, and by 1.93. A 2 cm cube, 8 cubic centimetres, weighs 15.44 to 19.20 g as chrysocolla and 32.40 g as malachite. That is why, in our judgement, two pieces of similar size and colour can often be told apart in the hand before any instrument is used.
On a scale, weigh in air and then suspended in water. Weight in water is mass times one minus one over density. A 20.00 g piece reads 9.64 to 11.67 g as chrysocolla and 15.06 g as malachite, or at least 14.44 g at the 3.6 floor that gem references give for impure or fibrous malachite. The gap is about 2.8 g. The 9.64 to 11.67 g figure is the same as on is chrysocolla the same as turquoise. The method is on how to measure specific gravity at home.
A reading in between means a mixture or a silicified piece. The International Gem Society gives Eilat stone, a mix of chrysocolla, malachite, turquoise and other minerals, a specific gravity of 2.8 to 3.2, which is 12.86 to 13.75 g on a 20.00 g piece. Chrysocolla-coloured chalcedony is quartz: 12.28 to 12.45 g at the quartz sheet's 2.59 to 2.65. Neither is wrong; each needs its own label.
Why do chrysocolla and malachite turn up together?
Both form in the oxidised parts of copper deposits, and each Handbook sheet names the other as an associate. Chrysocolla's Association field reads Malachite, tenorite, halloysite, nontronite; malachite's reads Azurite, cuprite, cerussite, chrysocolla, calcite. The International Gem Society notes chrysocolla may be mixed with malachite.
Method. The Association field of each of the 176 sheets in this site's reference set was extracted by script from pdftotext -layout text. Fourteen other sheets name chrysocolla, malachite among them. Twelve of the fourteen also name malachite: atacamite, azurite, brochantite, chalcophyllite, cuprite, dioptase, faustite, libethenite, olivenite, plancheite, pseudomalachite and shattuckite. Malachite is named on 30 sheets, pseudomalachite's name not counted, the figure on the malachite page.
Who each answer is wrong for. If your piece is blue, light in the hand and white-streaking, malachite is the wrong label. If it is green, banded and heavy, chrysocolla is. If it is both colours and weighs in between, it is probably both minerals, and the honest label names both. The species pages are chrysocolla and malachite. Nothing on this site is offered for sale; the wanted list is the only commercial route.