Goethite is hydrated iron oxide, (FeO(OH)). It is often formed from the breakdown of other iron minerals, and is a commonplace mineral. It was named in 1805 after J. W. von Goethe, a German poet and philosopher. This specimen comes from Looe, Cornwall, and is a fine specimen of a compact mass of radiating acicular crystals.
Anthophylite, Mg2Mg5Si8O22(OH)2 is an amphibole mineral, and classed as an asbestos. In this specimen which is a concretion, a grey fibrous aggregate of anthophylite is surrounding a nodule of phlogopite mica. This type of concretion is peculiar to Hefmanov in the Czech republic, and not surprisingly is called a Hefmanov ball.
Hematite, Iron oxide, Fe2O3 is the most important ore of iron. this botryoidal specimen is reniform ( kidney shaped ) and is commonly called Kidney ore. It's colour is black, but may vary between black and light brown. It's origin is only specified as Morocco.
Malachite is a copper carbonate mineral, Cu2CO3(OH)2 which forms as the result of weathering of copper ores. The specimen is an encrustation composed of a botryoidal covering of malachite on a crust of chrysocolla, which is a hydrated copper phylosilicate. The origin of the specimen is listed as from the Shaba province, Congo. The Shaba province only existed between 1971 and 1997, which indicates that this specimen was collected between those dates.
Magnesite, MgCO3, is a magnesium carbonate. The marketing name of citron chrysoprase is confusing, because chrysoprase is a silica mineral. This variety of magnesite gains its apple green colour from a nickel content, and for that reason is also called nickeloan magnesite. This half nodule has been polished, and the outer skin shows a deeper colour of green. In the Western Australia gold field, which is the origin of this specimen, there are numerous nodules, sometimes as much as a ton in weight. To reiterate, although this variety of magnesite is called "Citron chrysoprase" it has no silica content.