Pervasive white to light brown calcite, fine iron oxide boxwork
after sulfide veinlets and rare malachite staining, stratiform galena bands and erratic galena clumps or nodules are also present locally, as well as sporadic chalcedonic quartz in the limestone, hinting at a possible late-stage mineralizing event.
Overhead, a rare calcite formation called boxwork
looked like spiderwebs, neurons or fiberglass insulation, sealing us off from the world above.
Geologically, there are mineral resources, such as small nickel laterite deposits, thin or boxwork
gold veins, alluvial gold panning, clay and gemstones, that may only be economically feasible to develop at a smaller scale.
Silicification is characterized by a slightly boxwork
pattern, vuggy silica, relation to pyrite oxidation and association with clay minerals (mainly kaolinite).
This results in low ridges based on fractures but buttressed by iron oxides, silica or carbonate, like the fractures and adjacent sandstone impregnated by haematite-goethite and exposed in shore platforms on the west coast of Eyre Peninsula and the boxwork
patterns formed on some granite surfaces.
The matrix (50 vol%) is composed of gibbsite septa (boxwork
) and iron oxide accumulations which consist mostly of goethite.
but found in caves in the Knox of Bartow County is boxwork
. These thin, intersecting fins of calcite that protrude from wall and ceiling have traditionally been considered petromorphic but in some instances have been shown to be speleothemic.
The target being explored is the source for the cobble-sized quartz with sulfide boxwork
and coarse gold, which are common in the district.
calcite and pyrite have been observed: the host material here was probably clay that occupied the cavity prior to mineralization; dessication of the clay created fractures along which calcite crystals (at Plymouth) and pyrite crystals (at Biggsville) grew.
They include Piccadilly Station,Manchester City Art Gallery,Chorlton Park Housing, the Boxwork
and a National Trust property in Cumbria.
within the boxwork
alteration rinds increases outward from the nodules
Famous for its unique display of "boxwork
," an unusual formation resembling honeycombs, this cave was declared a national park by President Theodore Roosevelt in 1903.