(1) Those theories include that the haematite may have formed in a long-lasting lake or in a volcanic environment.(2) This colour change occurs over only a few metres on the ground and is probably related to the reduction of hematite to magnetite.(3) The red sandstone is made up of quartz grains coated with hematite , an iron oxide mineral that gives the stone a red colour.(4) Some hematite replacement erases all traces of the original mineralogy.(5) The third potential way the hematite could have formed is by oxidation of a mineral called magnetite in basalt and lavas.(6) Even if the hematite 's origin remains ambiguous, trace amounts of other minerals could serve as additional markers of past water.(7) Some samples have hematite in the calcite veins.(8) Carriers include the iron oxides magnetite and hematite .(9) The ironstone is locally represented by hematite matrix-supported vein quartz breccia.(10) The assemblage present included quartz, chalcopyrite, pyrite, sphalerite, magnetite, and hematite .(11) This was a steely gray specimen of the mineral hematite which, like many other stones, has a tradition of healing and additional magical influences.(12) The lakebed is believed to contain hematite , a crystalline iron compound usually formed in the presence of water.(13) Most, if not all, of these mines have likely produced specimen-quality hematite , goethite, and perhaps other minerals.(14) The fluids that precipitated the veins were a likely source for some of the iron that formed the hematite .(15) Like hematite , some goethite is pseudomorphic after a rhombohedral carbonate mineral.(16) Impressive blades and masses of lustrous micaceous hematite occur in localized quartz veins, and reniform goethite is found in the walls.
