Green Fluorite on Limestone

Description

A wide display face of translucent pale green Fluorite crystals rises from fine-grained grey limestone, with bright stepped faces catching the light.

Closely intergrown translucent Fluorite crystals form a gently arched face, with soft green colour through the centre and paler edges. Several faces show geometric step growth. The grey limestone is visible at the side, giving the cluster a natural contrast.

The stated Xiayang Mine locality is supplied with the specimen.

The crossing arrangement described above is an important part of the specimen’s silhouette. It lets the direction of individual crystals be followed through the group, with open spaces making their outlines more apparent. Intersecting crystals alone do not establish a specific twin law; here the description concerns the visible arrangement rather than a laboratory-confirmed crystallographic relationship.

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 Xiayang Mine, Yongchun County, Quanzhou Prefecture, Fujian 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 165 × 100 × 53 mm, with a recorded weight of 919 g. 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.