Chlorite in Quartz

Quartz with Chlorite inclusions is quartz (silicon dioxide, SiO₂) that contains internal or coating inclusions of chlorite-group minerals. Chlorite is a group of hydrous aluminum, magnesium, iron silicate minerals characterized by sheet (phyllosilicate) structure. The most common chlorite species are clinochlore (magnesium-rich) and chamosite (iron- rich). The green color of the inclusions is due to the chlorite minerals; variations in hue (moss green, forest green, pastel green) derive from differences in iron vs magnesium content, degree of crystallinity, and quantity/distribution of inclusions. In Pakistan material, the quartz is often very clear (gem-transparent or nearly so) with sharp terminations and the chlorite often forms internal “phantoms” (ghost-shapes), coatings, or mossy patterns.

Formation occurs when quartz crystals grow in an environment where chlorite minerals are present in the mineralizing fluids or as preexisting phases in the rock, or chlorite forms early or simultaneously and gets encapsulated by later quartz growth. Some specimens are “faden” quartz—crystals with a thread-like line of growth—that include chlorite along that line (e. g. Kharan District, Baluchistan). Localities in Pakistan where this material is known include Shigar Valley (Gilgit-Baltistan), Haramosh Mountains, Dera Ismail Khan, Kharan District in Baluchistan, Obodda / Taftan & environs.

The host rock is generally quartz veins or pockets, often in alpine-type or high mountain environments, sometimes linked with hydrothermal activity or metamorphic settings. Quartz is the host mineral; chlorite is either included within or coating the quartz, sometimes forming phantoms or layering inside.