Tremolite
Tremolite is a silicate mineral prized by collectors for its exceptional color range, with several world-class Chinese localities.
About Tremolite
Tremolite is a silicate mineral in the amphibole group (calcium amphibole subgroup) and has the chemical formula □Ca2Mg5(Si8O22)(OH)2. It crystallizes in the monoclinic system and is one of the most visually varied minerals in the collector market. Its combination of structural character and global distribution make it a recognized species in both systematic and aesthetic collections.
Identification & care
Crystals commonly develop as bladed, prismatic crystals; fibrous (asbestiform); massive, granular; radiating and columnar aggregates. Its color range is broad, including white, colorless, pale green, pale grey, pale yellow, and fibrous variety = white asbestos. The luster is vitreous, silky (fibrous), pearly, the streak is white, and specimens range from transparent to translucent. The cleavage is perfect on {110}, two directions at ~56° and 124° (characteristic amphibole cleavage). The fracture is uneven, splintery (fibrous), which aids identification.
Collector context
How it forms
Tremolite forms in metamorphosed dolomitic limestones (in marbles and calc-silicate rocks); also in ultramafic/ophiolitic rocks; hydrothermal veins in mafic rocks. It is commonly found in association with dolomite, calcite, diopside, talc, phlogopite, chlorite, forsterite.
Classic Chinese localities
Documented Chinese occurrences are recorded at Shangbao Mine, Jiama Cu-polymetallic deposit and Xianghualing Sn-polymetallic ore field, among others.
Why collectors care
Collectors pursue Tremolite for the clarity of its crystal form and, in good material, saturated color that reads instantly across a display case. A well-terminated tremolite on clean matrix photographs well, identifies quickly, and anchors a cabinet piece. Top Chinese specimens over the last two decades have reset the bar for what tremolite looks like at collector grade.
What affects value
Value in Tremolite is assessed, in typical order of weight, against: (1) locality provenance; (2) size relative to the species norm; (3) crystal form and termination sharpness; (4) color saturation and zoning; (5) transparency and internal clarity; (6) matrix quality and aesthetic balance; (7) condition (absence of damage, chips, or repair). Cleaning quality and verified locality documentation act as multipliers across the above.
Naming history
The name Tremolite has a specific etymological and historical context — see Mindat's reference entry for provenance details. We have retained naming data at the record level; published prose is paraphrased from factual fields rather than copied from source.