Brown / Orange / White Quartz Crystal with Moderate–High Sulfidation – Victorian Goldfields: Specimen 15

Notable Features

This quartz crystal specimen weighs 136 g and measures approximately 7.5 × 6.5 × 6 cm. It displays a moderate–high sulfide level, with an attractive mix of brown, orange, and white crystal zones.

Notable features include:

• Compact quartz crystals with earthy orange staining

• Metallic sulfide inclusions adding texture and depth

• Strong contrast between pale quartz and darker iron oxide alteration

Sulfide Level

Moderate–High – Fine-grained sulfides are intergrown with the quartz, visible as metallic specks and patches, accompanied by oxidation staining. Likely minerals include pyrite and arsenopyrite, with traces of chalcopyrite possible.

See how we rate sulfide levels by visiting our FAQ section.

Mineral Assemblage

• Quartz – Brown to white, crystalline habit with iron-stained surfaces

• Pyrite – Likely present as fine inclusions

• Chalcopyrite – Possible brassy flecks within stained zones

• Arsenopyrite – Fine metallic specks in fractured areas

• Iron oxides – Orange and reddish staining from weathering

• Trace gold and silver (mostly refractory, rare visible free gold possible)

Note: Not every specimen contains the full mineral assemblage above. Minerals may appear in varying amounts, and each specimen may only feature a subset. Each piece is unique and chosen for its visual appeal and geological character.

Geological Story

This specimen formed during the Silurian Period (~440–420 million years ago), when tectonic forces fractured submarine fan sediments in the Victorian Goldfields. Silica-rich hydrothermal fluids surged through these fractures and cooled slowly, crystallizing into quartz rather than the massive milky quartz common in Victoria.

Depending on conditions, the quartz developed as brown, orange, and white crystal forms, with sulfides such as pyrite, chalcopyrite, arsenopyrite, stibnite, and tetrahedrite deposited alongside. Over time, iron oxides added further color and contrast.

The Victorian Goldfields were historically mined for gold, silver, and antimony. While most of the precious metals are refractory and locked within sulfides, rare specimens containing visible free gold are known.

This specimen is not sold as “gold ore.” It is a collector’s specimen, chosen for its moderate–high sulfide character, earthy iron staining, and mix of crystal colors and for its geological significance as a fragment of one of Australia’s most famous gold regions.