Purple Octahedral Fluorite on Banded Quartz-Calcite · No. 1

Description

A closely grouped cluster of lavender-purple octahedral Fluorite crystals rises across creamy banded Quartz-Calcite. Deeper violet outlines and colour zoning add definition to the translucent triangular faces.

You will receive the specimen shown.

The De’an Mine locality and Quartz-Calcite matrix identification are supplied with this specimen.

The octahedral description refers to an eight-faced crystal form. In a group, some faces can be partly hidden by neighbouring growth, so the geometry is read through the visible outlines as well as the individual surfaces. This is a useful contrast with the more familiar cubic habit when collecting different Fluorite forms.

The accompanying Calcite contributes a different crystal habit and surface character to the specimen. Its lighter or more translucent areas provide a contrast with the other recorded growth, allowing their separate outlines to be followed. The association is worth appreciating as a whole, with the arrangement and contact between the minerals adding detail beyond the featured crystals alone.

The accompanying Quartz brings a silicate crystal habit into the association. Its surfaces and crystal outlines contrast with the featured mineral, giving the specimen more than one kind of growth to examine. The way the minerals occupy the same piece is part of its character: the setting retains their natural relationship and adds depth to the overall display.

Fluorite is calcium fluoride and crystallises in the cubic system. Cubes and octahedra are among its familiar forms, but intergrowths, modified faces and changes during growth can produce much more complex outlines. This combination of recognisable geometry and considerable variation makes Fluorite a rewarding mineral to collect by both crystal habit and locality.

Fluorite can be colourless or show a wide range of colours, sometimes within one specimen. Transparency, crystal thickness and illumination influence how those colours appear. Its glassy faces contrast with more textured areas and any accompanying matrix. Colour zoning and fluorescence are separate properties; a particular response under ultraviolet light should only be expected where it has been recorded for the individual piece.

The recorded origin is De’an Mine, Jiangxi Province, China. Within a collection of Fluorite specimens, this locality gives the piece a geographical identity alongside its particular crystal habit and natural setting.

The specimen measures 76 × 50 × 30 mm. The proportions give a useful guide to its place in a display, with the individual crystal arrangement and mineral association remaining the principal points of interest.

Fluorite has well-developed cleavage and should be supported by its stable matrix or mount. Avoid pressing on projecting cubes or corners. A secure indoor position allows the natural geometry and colour to be appreciated while keeping the exposed growth protected.