Lapis Lazuli
Lapis Lazuli is a feldspathoid mineral recognized among collectors for its crystal form and distribution.
About Lapis Lazuli
Lapis Lazuli is classified as a feldspathoid mineral in the sodalite group (lazurite component) and has the chemical formula Rock: Lazurite Na7Ca(Al6Si6O24)(SO4)(S3)·H2O + Calcite CaCO3 + Pyrite FeS2. It crystallizes in the isometric system and holds a steady position among feldspathoid species. 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 rock — massive aggregates; lazurite dodecahedral crystals are rare standalone specimens. Its color range is broad, including deep intense blue, violet-blue, gold pyrite flecks, and white calcite streaks. The luster is dull to waxy on polished surfaces, the streak is blue to pale blue, and specimens are typically opaque. The cleavage is n/a (rock). The fracture is uneven (rock), which aids identification.
Collector context
How it forms
The geological setting for Lapis Lazuli is typically high-grade regional metamorphism of evaporite-bearing limestone sequences (meta-evaporites); requires calcium, sodium, sulfur, and aluminum-rich protolith. It is commonly found in association with calcite, pyrite, diopside, albite, afghite, wollastonite, scapolite.
Why collectors care
Lapis Lazuli is a frequently-sought species in serious collections because its habit is recognizable, its color often strong, and its best examples unmistakable even at a distance. Chinese material has driven much of the recent visual shift in the species — sharper crystals, deeper colors, cleaner matrix.
What affects value
Value in Lapis Lazuli 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 Lapis Lazuli 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.