Tiny rhombs of colourless calcite with opaque white laumontite on fibrous mordenite. Laumontite, Mordenite, Calcite, Waitekauri, Hauraki District, Waikato Region, North Island, New Zealand. Width of view 11mm.
Tucked away in a quiet valley in the Coromandel Peninsula, the area around Waitekauri is now a peaceful landscape of regenerating bush, but its ghostly remnants of mining machinery tell a story of immense gold rush fever. In the late 19th century, this was a booming town and one of...
Hokitika was founded during the West Coast gold rushes in 1864. Examples of gold from the local rivers can be purchased at tourist shops. Below: Gold, Hokitika, Westland District, West Coast Region, New Zealand. Nugget measures 8mm across.
Hokitika, on the west coast of the South Island, is a town whose entire identity, from its deep Māori history to its explosive European settlement, is inextricably linked to its unique geology and mineral wealth. 1. The Geological Setting: An Engine of Creation and Erosion The geology of the Hokitika...
Hokitika was founded during the West Coast gold rushes in 1864. Examples of gold from the local rivers can be purchased at tourist shops. Below: Gold, Hokitika, Westland District, West Coast Region, New Zealand.
Siderite is a very common mineral, in lustrous or iridescent deep brown forms, rarely in paler brown translucent balls. Generally it is in sheaf-like bundles, occasionally in ‘bow-ties’. It does occur in rhombs, often with curved multiple surfaces, and these are frequently hollow, with maybe a chabazite or two inside....
Siderite is a very common mineral, in lustrous or iridescent deep brown forms, rarely in paler brown translucent balls. Generally it is in sheaf-like bundles, occasionally in ‘bow-ties’. It does occur in rhombs, often with curved multiple surfaces, and these are frequently hollow, with maybe a chabazite or two inside....
Phillipsite has been found as crystals in the classic phillipsite form as larger (1mm) crackled clear crystals, associated with barite and clear barrel-shaped chabazite. It also occurs as minute creamy crystals with analcime and chabazite, also small. The exact species has not been confirmed. Below: Phillipsite, Bickers Quarry (Simpkins Quarry),...
Black magnetite octahedra, some with traces of chlorite on their faces, some of which are stepped. Some magnetite crystals are completely encased in chlorite. Blocky orthoclase crystals form part of the cavity lining. Brown sheaf or club-shaped siderite, yellow hexagonal chabazite-Na, and needles of apatite coated with chlorite. Below: Magnetite,...
Gypsum tends to usually occur alone or with barite, chabazite-Na and analcime in the more weathered rock. It forms sprays of clear needles, or larger flat crystals. Below: Gypsum, chabazite-Na, Bickers Quarry (Simpkins Quarry), Tokatoka, Kaipara District, Northland Region, North Island, New Zealand. Width of view 6mm.
Gypsum tends to usually occur alone or with barite, chabazite-Na and analcime in the more weathered rock. It forms sprays of clear needles, or larger flat crystals. Below: Gypsum, siderite and chlorite, Bickers Quarry (Simpkins Quarry), Tokatoka, Kaipara District, Northland Region, North Island, New Zealand. Width of view 6mm.
Chabazite-Na (“herschelite“) crystals are found in many vugs, as single yellowish, cream, white or colourless hexagonal plates, with striated prism faces and matt-finish flat surfaces. Under magnification the flat surfaces are shown to be made of many tiny points. These crystals are splendid examples of the “herschelite” crystal shape, and...
