The term “Ruby Jade” is a marketplace designation, not a recognized mineral species, which causes frequent confusion among consumers and collectors. This name is most often applied to a striking, naturally occurring composite rock that pairs a red mineral with a green matrix material. Due to the ambiguity of the name, the material sold under this trade moniker can vary significantly, ranging from a naturally formed rock to a heavily treated or dyed version of actual jade.
What Mineralogists Call “Ruby Jade”
Mineralogically, the material most commonly referred to as “Ruby Jade” is a composite rock known as ruby-in-fuchsite. This rock is a blend of two distinct minerals: the red inclusions are opaque ruby (a variety of corundum), and the green matrix is fuchsite (a chromium-rich variety of muscovite mica). The red color of the ruby and the green hue of the fuchsite are both caused by trace amounts of chromium within their respective chemical structures. The ruby crystals found within this matrix are typically opaque and not of gem quality, unlike the transparent, faceted rubies used in traditional fine jewelry.
Another similar, though less common, material sometimes incorrectly grouped under this name is ruby-in-zoisite, which features the same opaque ruby but is embedded in a green zoisite matrix. In cases where the material is actual jade, the “ruby” designation refers to highly pigmented or dyed jadeite or nephrite. True jade, whether jadeite or nephrite, is a single mineral or rock type, whereas ruby-in-fuchsite is a rock composed of two different intergrown mineral types.
Geological Formation and Primary Sources
The formation of ruby-in-fuchsite involves a high-pressure geological process known as regional metamorphism, often combined with hydrothermal alteration. This process occurs deep within the Earth’s crust, typically where tectonic plates collide, subjecting existing rocks to intense heat and pressure. During this transformation, the ruby crystals grow and become encapsulated within the developing green fuchsite matrix. The chromium that gives both minerals their color is a necessary element in the host rock for this specific combination to form.
The resulting composite rock is extracted directly from the bedrock. The largest commercial source for ruby-in-fuchsite today is India, particularly from the states of Karnataka, Tamil Nadu, and Orissa. Deposits of this material are also found in several other global locations, including Brazil, Russia, Pakistan, and Madagascar. The presence of other minerals, such as kyanite or snow quartz, can sometimes be observed, giving each regional source a unique texture.
Distinguishing Characteristics and Treatments
A defining characteristic of ruby-in-fuchsite is its stark contrast of mottled red and vibrant green colors, which are unevenly distributed across the stone. The physical properties of the material are highly variable due to its composite nature. While the ruby inclusions are hard, measuring 9 on the Mohs scale, the surrounding fuchsite matrix is significantly softer, typically ranging from 5 to 5.5. This difference in hardness can affect the polishing quality and durability of the finished stone.
The stone is generally opaque to translucent and exhibits a vitreous to pearly luster after being polished. For the composite material, treatments are minimal, usually involving only cutting and polishing to enhance its natural appearance. However, the ruby component itself may undergo standard ruby treatments such as heat or fracture-filling, though this is less common for the opaque, matrix-grade material. Conversely, if the term “Ruby Jade” is applied to actual jade, it is often heavily treated with bleaching, polymer impregnation (Type B jade), or dyeing to create the desired red color.
Commercial Applications and Value
Ruby-in-fuchsite is primarily used in the production of decorative objects, beads, and jewelry components such as cabochons. Because of its composite nature and the variable hardness of its constituent minerals, it is not typically suitable for faceting into traditional gemstone cuts. The material is popular for ornamental carvings and polished spheres, where the juxtaposition of the deep red ruby and the bright green matrix is prominently displayed.
The market value of ruby-in-fuchsite is determined by several factors, rather than a standard per-carat price. Stones that feature a higher density of ruby inclusions and a more vibrant, deep green fuchsite matrix command a greater price. The material is relatively affordable, with smaller cabochons often ranging from $10 to $50. The value is higher for untreated material, although the opaque nature of the ruby means it is less frequently subjected to the high-heat treatments common for gem-quality rubies.