FUCHSITE – Lustrous Green Mica Blades on Matrix, Jacobina, Bahia, Brazil

This is a naturally formed specimen of Fuchsite, the vivid green, chromium-bearing variety of muscovite mica, showing well-developed lamellar (platy) crystals typical of the species. The individual blades are clearly separated and display flat, well-defined cleavage faces that catch the light with a bright pearly-to-vitreous luster, a hallmark of well-crystallized phyllosilicate minerals.

The intense green coloration is immediately eye-catching and is one of the defining features of this variety, contrasting nicely against the paler, more translucent portions of the blades.

The specimen comes from the Jacobina gold district in the state of Bahia, northeastern Brazil, one of the most significant gold-mining regions in South America. Here, Fuchsite occurs as chromium-rich muscovite intergrown with quartz-pebble conglomerates and quartzite hosting the region's gold mineralization; the fuchsite typically forms a distinctive green halo around the gold-bearing reefs. The Jacobina mining complex remains an active operation today, run at industrial scale for gold extraction, which makes well-formed, clean mineralogical specimens like this one a pleasant byproduct rarely offered as standalone display pieces.

A naturally attractive and scientifically interesting piece, ideal for mineralogical collections, display, and for anyone who appreciates the natural beauty of phyllosilicate minerals.

Fuchsite is the chromium-rich green variety of muscovite, a common mica belonging to the phyllosilicate (sheet silicate) group. Its intense green color is caused specifically by the presence of trivalent chromium ions (Cr³⁺) substituting for aluminum within the octahedral sites of the mica's crystal lattice; the higher the chromium content, the more saturated the green hue. Like all micas, Fuchsite grows in thin, flexible lamellar sheets with perfect basal cleavage, which is clearly visible in this specimen as flat, reflective crystal faces stacked in blade-like aggregates. In the Jacobina district, Fuchsite forms through regional hydrothermal alteration associated with gold mineralization, developing as a halo of chromium-enriched mica within Paleoproterozoic quartz-pebble conglomerates and quartzites.

• Formula: K(Al,Cr)₂(AlSi₃O₁₀)(OH)₂
• Key chemical elements: Potassium, Aluminum, Chromium, Silicon, Oxygen
• Hardness (Mohs scale): 2.5–3
• Mineral class: Silicates (Phyllosilicates)
• Crystal system: Monoclinic
• Crystal habit: Lamellar, tabular, foliated blades
• Formation: Hydrothermal/metamorphic alteration within gold-bearing quartz-pebble conglomerates
• Color: Intense green, caused by Cr³⁺ substitution for aluminum

Fuchsite is named after the German mineralogist Johann Nepomuk von Fuchs, and owes its vivid green color to chromium (Cr³⁺) substituting for aluminum within the mica structure. In the Jacobina gold district of Bahia, Fuchsite plays a special role: geologists and miners have long used the presence of green fuchsite-rich haloes surrounding the ancient quartz-pebble conglomerates as a visual indicator of nearby gold mineralization, since the chromium-bearing mica tends to concentrate around the same hydrothermal alteration zones that hosted the gold. The Jacobina basin itself is a Paleoproterozoic sedimentary formation whose gold-bearing conglomerates have been compared geologically to the famous Witwatersrand basin in South Africa.

In crystal healing traditions, green Fuchsite is associated with the heart chakra and is said to promote emotional balance, compassion, and a sense of renewal. It is also traditionally linked to physical vitality, resilience, and the ability to release stress or negative energy accumulated in the body. Some practitioners use Fuchsite as a stone of growth and flexibility, mirroring its flexible, lamellar crystal structure as a symbol of adaptability in life. As with all mineral specimens, these interpretations are not scientifically proven.

Photos: All photographs are taken under professional lighting conditions to accurately highlight crystal structure, color and detail. However, slight variations in tone and appearance may occur depending on screen calibration and ambient lighting conditions.

Shipping: is handled through selected reliable express couriers, with fast delivery (often 1–2 business days within Europe), full tracking, insurance coverage and professional protective packaging, as confirmed by customer feedback and reviews.

Multiple purchases can be consolidated into a single shipment, including items from different auctions or separate orders, by simply contacting us to arrange combined shipping. For high-value specimens, direct delivery by appointment is also available, either at home or at major European mineral shows and fairs.