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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: 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: 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: 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: 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: 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: 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: 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: 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: 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.

9 Apr 2024: Chlorite crystal structure, CrystalMaker. Formula. (Mg,Fe. 2+. ,Fe. 3+. ,Mn,Al). 12. [(Si,Al). 8. O. 20. ](OH). 16. Structure. Sheet silicate. Crystal System. Crystal system: monoclinic () (-). Physical Properties. Colour in hand specimen: green.

9 Apr 2024: Dolomite in hand specimen. Dolomite crystal structure, CrystalMaker. Formula. CaMg(CO. 3. ). 2. Structure. Non-silicate. Crystal System. Crystal system: trigonal (-). Physical Properties. Colour in hand specimen: white, often tinged with yellow or

9 Apr 2024: Fluorite crystal hand specimen, purple hue. Fluorite crystal structure (cubic), CrystalMaker. Formula. CaF. 2. Structure. Non-silicate. Crystal System. Crystal system: cubic. Physical Properties. Colour in hand specimen: extremely variable:

9 Apr 2024: Anhydrite crystal structure, CrystalMaker. Formula. CaSO. 4. Structure. Non-silicate. Crystal System. Crystal system: orthorhombic (). Physical Properties. Colour in hand specimen: white or colourless when pure. Cleavage: two at 90. Hardness: 3-3.5.

9 Apr 2024: Mica, muscovite. Crystals of muscovite with basal cleavage. Crystals of muscovite, colourless. Muscovite crystal structure (a sheet silicate), CrystalMaker. Formula. K. 2. Al. 4. [Si. 6. Al. 2. O. 20. ](OH,F). 4. Structure. Sheet silicate. Crystal