moolooite

{{Infobox mineral

| name = Moolooite

| image = Moolooite-91983.jpg

| imagesize = 260px

| caption = Blue massive moolooite (field of view 12 mm)

| category = Oxalate mineral

| formula = {{chem2|Cu(C2O4) · 0.4H2O}}

| IMAsymbol = Moo{{Cite journal|last=Warr|first=L.N.|date=2021|title=IMA–CNMNC approved mineral symbols|url=https://www.cambridge.org/core/journals/mineralogical-magazine/article/imacnmnc-approved-mineral-symbols/62311F45ED37831D78603C6E6B25EE0A|journal=Mineralogical Magazine|volume=85|issue=3|pages=291–320|doi=10.1180/mgm.2021.43|bibcode=2021MinM...85..291W|s2cid=235729616|doi-access=free}}

| strunz = 10.AB.15

| system = Orthorhombic

| class = Dipyramidal (mmm)
H-M symbol: (2/m 2/m 2/m)

| symmetry = Pnnm

| color = green

| gravity = 3.43 (calculated)

| density = 2.6

| references = [https://www.mineralienatlas.de/lexikon/index.php/MineralData?mineral=Moolooite Mineralienatlas]

}}

Moolooite is a rare blue-green mineral with the formula Cu(C₂O₄)·n(H₂O) (n<1) (copper(II) oxalate hydrate). It was discovered in Bunbury Well, Mooloo Downs station, Murchison, Western Australia in 1986.{{cite journal |last1=Clarke |first1=R.M. |last2=Williams |first2=I.R.|title=Moolooite, a naturally occurring hydrated copper oxalate from Western Australia|journal=Mineralogical Magazine |volume=50 |year=1986 |pages=295–298 |url=http://rruff.geo.arizona.edu/doclib/mm/vol50/MM50_295.pdf |issue=356 |doi=10.1180/minmag.1986.050.356.15|bibcode=1986MinM...50..295C|s2cid=54527532 }} It has an orthorhombic crystalline structure, and is formed by the interaction of bird guano with weathering copper sulfides.

A second occurrence is reported from the Sainte-Marie-aux-Mines silver mining district of Vosges Mountains, France.