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6 Jun 2024: Tosca mentioned that on Mars there’s plenty of magnetite and part of his studies have involved trying to replicate the mechanisms that might have led to the formation of this ... but a dissolution reprecipitation transformation, simply due to its

6 Jun 2024: Almeida, Pádraig Ó Conbhuí, and Valera P. Shcherbakov. 2017. “Stability of Equidimensional Pseudo–single-Domain Magnetite over Billion-Year Timescales.” Proceedings of the National Academy of Sciences 114 (39): 10356–60. ... 2019. “Secondary

6 Jun 2024: Search site. Publications. Uploading Images. Members of the Department can attach an image to a publication by clicking on the title of the publication in the listing below. Please note: all images attached to a publication will be visible on

9 Apr 2024: Browse Items (7 total). Tags: igneous. Sort by:. Formula Ca5(PO4)3(OH,F,Cl) Structure Non-silicate Crystal System Crystal system: hexagonal (-) Physical Properties Colour in hand specimen: green, white, yellow, blue brown etc.Hardness: 5 Optical

9 Apr 2024: Strongly pleochroic in reddish brown and pale straw. Often associated with small grains of an opaque accessory mineral, probably magnetite.

9 Apr 2024: Galena crystal structure, with large yellow sulfur and small purple lead symbols. Galena in hand specimen. Formula. PbS. Structure. Non-silicate. Crystal System. Crystal system: cubic. Physical Properties. Colour in hand specimen: lead grey. Streak:

9 Apr 2024: Gypsum single crystal hand specimen, monoclinic symmetry apparent. Milky, opaque gypsum with twinned crystal habit. Gypsum crystal structure showing monoclinic symmetry, CrystalMaker. Formula. CaSO. 4. 2H. 2. 0. Structure. Non-silicate. Crystal

9 Apr 2024: Halite cubic crystal structure with large Cl. -. anions (green) and small Na. cations (yellow). This mineral is commonly known as rock salt. Formula. NaCl. Structure. Non-silicate. Crystal System. Crystal system: cubic. Physical Properties. Colour

9 Apr 2024: Sphene crystal structure, CrystalMaker. Formula. CaTi[SiO. 4. ](O, OH, F). Structure. Orthosilicate. Crystal System. Crystal system: monoclinic (). Physical Properties. Colour in hand specimen: colourless, yellow, green, brown or black. Cleavage: one

9 Apr 2024: Alteration to magnetite and serpentine, particularly along the curving cracks. Cracks across the thin-section, could be due to expansion of the rock as the olivine was altered.

9 Apr 2024: Garnet (euhedral) in hand specimen. Formula. (Mg,Fe,Ca). 3. Al. 2. Si. 3. O. 12. Structure. Orthosilicate. Crystal System. Crystal system: cubic. Physical Properties. Colour in hand specimen: typically red. Cleavage: none. Hardness: 6-7.5. Optical

9 Apr 2024: Pyrite crystals, with metallic lustre. Pyrite crystals within quartz. Pyrite cubis crystal structure, showing octahedral coordination of Fe by S. Formula. FeS. 2. Structure. Non-silicate. Crystal System. Crystal system: cubic. Physical Properties.

9 Apr 2024: Zircon crystal structure (tetragonal), CrystalMaker. Zircon is a common accessory mineral of many igneous rocks. Pleochroic haloes are formed by damage to the crystal lattice of enclosing minerals by the radioactive decay of elements such as Th and

9 Apr 2024: Alteration. Zonation. Accessory minerals:. - Sphene. - Magnetite. - Apatite. Rock History.

9 Apr 2024: Alteration to magnetite and serpentine, particularly along the curving cracks. Cracks across the thin-section, could be due to expansion of the rock as the olivine was altered.

9 Apr 2024: Apatite crystal structure, CrystalMaker. Formula. Ca. 5. (PO. 4. ). 3. (OH,F,Cl). Structure. Non-silicate. Crystal System. Crystal system: hexagonal (-). Physical Properties. Colour in hand specimen: green, white, yellow, blue brown etc. Hardness: 5.

9 Apr 2024: Epidote crystal structure. Formula. Ca. 2. Al. 2. O(Al,Fe. 3+. )OH[Si. 2. O. 7. ][SiO. 4. ]. Structure. Orthosilicate. Crystal System. Crystal system: monoclinic (-). Physical Properties. Colour in hand specimen: green. Cleavage: one, perfect.

9 Apr 2024: Quartz single crystal, no cleavage, conchoidal fracture. Quartz prisms, vitreous lustre. Quartz prisms (roughly hexagonal habit). Quartz crystal structure (trigonal unit cell), CrystalMaker. Formula. SiO. 2. Structure. Framework silicate. Crystal

9 Apr 2024: Single crystal calcite hand specimen. Small calcite crystals growing from a free surface. Milky single crystal of calcite. Calcite crystal structure, CrystalMaker. Formula. CaCO. 3. Structure. Non-silicate. Crystal System. Crystal system: trigonal (-

9 Apr 2024: Olivine hand specimen, no cleavage. Olivine crystal structure, CrystalMaker. Formula. (Mg,Fe). 2. [SiO. 4. ]. Structure. Orthosilicate. Crystal System. Crystal system: orthorhombic () (-). Physical Properties. Colour in hand specimen: pale green.