( Fr- lapis-lazuli; Ger- Lasurstein; Nor- lapis lazul/lasurstein; Rus- )
A. Lapis lazuli from Afghanistan (width - ca. 4.5 cm). (© photo by D.L. Brittain)
B. Lapis lazuli from near Lake Baikal, Russia (height - 7.3 cm). Ariel. (© photo by Jeffrey A. Scovil)
C. Lapis lazuli cuff links, tie tack and necklace (length - ca. 45 cm). R.V. and F.S. Dietrich collections. (© photo by D.R. Fisher)
DESCRIPTION: Most lapis lazuli comprises a
crystalline aggregate made up largely of blue lazurite (a mineral of
the sodalite group), plus noteworthy amounts of macroscopic white
calcite and pyrite grains. Some lapis lazuli contains one or more of
the other minerals
of the sodalite group -- hauyne, nosean, and sodalite per se --
along with or in lieu of the lazurite. In addition, some lapis
also contains minor amounts of phlogopite mica, diopside, amphibole,
etc., each of which may or may not be macroscopically
The lapis lazuli widely considered to be of highest quality contains
small, rather evenly distributed pyrite grains and relatively
small percentages of or no calcite. Some lapis lazuli
color-laminated in different shades of blue.
Properties of lazurite follow:
Colors - typically azure- to deep blue, rarely purplish or greenish blue
Light transmission - typically subtranslucent to opaque, but some is translucent in thin fragments
Luster - vitreous, waxy or dull
Miscellany - when the blue constituent, whatever sodalite mineral it is, is attacked by HNO3 (nitric acid), H2S, which has the odor of rotten eggs, evolves.
USES: Jewelry, carvings, ... etc. In addition, lapis lazuli, along with other gemrocks such as malachite, rhodochrosite and sugilite, has been used in mosaics and high quality intarsias (gemstone inlays) used in pendants, box panels, etc.; these uses have noteworthy ancient precedents -- e.g., lapis lazuli, along with nacre, was used in marquetry found in an ancient tomb in Ur, Chaldea (now southern Iraq). -- See the illustrations at the top of the plate opposite page 64 in Da Cunha (1989). Special attention is directed to the well-illustrated article "The celestial stone" (Covington, 2013): Several fine pieces made of or featuring lapis are shown, and the description the "Making Lapis Paint" (op. cit., p. 4) serves to emphasize another use of this GemRock.
OCCURRENCES: Diverse -- e.g., as veins, layers or lenses in so-called contact metamorphosed impure calcareous and/or dolomitic rocks with or without associated evaporite units; at least some lapis lazuli appears to have been formed primarily in response to thermal metamorphism accompanied by little, if any, hydrothermal and/or pneumatolytic activity.
NOTEWORTHY LOCALITIES: Along the Kokcha River, near Sar-e-Sang, Badakhshan Province, Afghanistan; near Sludyanka on Lake Baikal, Siberia, Russia; in eastern Chile, near the Argentina border, approximately 45 miles northeast of Illapel, State of Coquimbo; near Lake Harbor, southern Baffin Island, Canada; in San Bernardino County, California; and near the timberline of North Italian Mountain, of the Sawatch Range of the Rockies, approximately 35 miles northeast of Gunnison, Gunnison County, Colorado. Shigley et al. (2000) tabulate localities and pertinent references for localities from which lapis lazuli was recovered during the 1990s.
Lapis lazuli from Afghanistan has long been considered to set the quality standard. Some connoisseurs, however, consider certain lapis lazuli from other localities to be of nearly, if not truly, equal quality -- e.g., some lapis lazuli mined in the Coquimbo Region or the Chilean Andes since the early 1900s is considered virtually as good as the so-called top-grade Afghanistan material. -- This lapis lazuli is, by the way, extremely interesting mineralogically; it is composed largely of blue lazurite, with noteworthy calcite, diopside, haüyne, pyrite, scapolite, and wollastonite along with trace amounts of afghanite, allanite, arsenopyrite, chalcopyrite, epidote, plagioclase feldspar, pyrrhotite, siderite, sodalite and tremolite as accessory minerals -- (see Coenraads and deBon, 2000).
REMARKS: In pre-Middle Ages literature, lapis lazuli was usually referred to as sapphire (or its equivalent)-- e.g., in publications by Theophrastus and Pliny, the Elder. This mistaken identity is so-to-speak perpetuated in many modern Bibles – which seems easily accounted for by the likelihood that commonly used translations of the Bible were by persons with insufficient geological knowledge of the region. In any case, the current name for lapis lazuli appears not to have come into use until the Middle Ages when it was derived from the ancient Persian "lazhuward" (blue) and/or Arabic "lazaward" (Heaven, sky, or blue).
Some lapis lazuli, especially that with relatively large amounts of included calcite, has been dyed to make it appear bluer; in some cases, the dye has been applied selectively to the white constituent(s). Frequently, the dye can be detected by hand lens observation; alternatively one can rub the material with a swab soaked in a solvent such as acetone or fingernail polish remover -- the swabs will take on a blue discoloration if the material has been dyed. Some dyed lapis lazuli has been waxed, oiled or coated with a polymer to improve its luster and/or to cover and preserve applied dye. Such coatings may have to be removed -- e.g. by heating the spot to be checked with a probe or dissolving the area to be tested with some organic solvent -- before checking to see if the given piece has been dyed.
Naturally greenish blue lapis lazuli from some localities seems to take on a more desirable dark blue appearance after exposure to the elements (light, etc.), and, in some cases, a dark blue color has been produced by so-to-speak washing the greenish material with H2CO3 or other dilute acids. In general, however, lapis lazuli jewelry, carvings (etc.) should be kept away from heat and chemicals, especially if there is any chance it has been dyed to enhance its color.
Afghanistan lapis lazuli was found in the 7th century B.C.archaeological site designated as the ancient city of Mehrgarh, in the Indus Valley of what is now Pakistan. As early as the 6th century B.C., lapis lazuli from the Badakhshan mines was transported, chiefly by camel caravan, to China, India and Tibet, and later to Egypt, where it was fashioned into scarabs and amulets, and shortly thereafter it reached other Mediterranean countries. Three facts mentioned by Coenraads and deBon (2000) in support of widely recorded statements such as those just reiterated support the contention that lapis lazuli is one of the first gemstones used as a decorative and gem stone: 1.It is mentioned in Chinese annals of the 8th and 6th centuries BC; 2.lapis lazuli-bearing Sumerian court jewelry, carvings, etc. were found in the royal tomb of Queen Pu-abi (circa 2500 BC), Ur,Iraq (see colored photo in Douglas, 1980, p,782); and 3.lapis lazuli constitutes the eyebrows and areas around the eyes of the gold mask of the mummy of Tutankhamun (1361-1352 BC).
Lapis lazuli was ground to produce ultramarine pigment as early as the 11th century A.D. and was used by, for example, the famous "old masters" (Renaissance painters) inter alia. In fact, that use continued until Jean Baptiste Guimet's inexpensive substitute -- a so-called ultramarine pigment -- was developed in the 1820s and subsequently became widely available (Adolph Knopf, lecture notes, 1948).
Marco Polo visited the famous Afghanistan mines in the late 1200s.
When and where the term "heaven stone," or some variant thereof, was first applied to lapis lazuli seems lost in antiquity. In any case, when many people look at a piece of jewelry or something else fashioned from a fine piece of lapis lazuli, they seem almost inevitably to compare its overall deep blue hue with the evening sky and its scattered grains of goldlike pyrite to the stars, and some people even note that the white calcite areas resemble clouds.
A post-September 11, 2001 advertizement for a "Peace Pin" seems to me to be an incongruent absurdly -- perhaps even ghoulishly -- conceived piece of jewelry. My belief is based on the fact that the pin is a polished hemisphere of lapis lazuli, very likely from Afghanistan, apparently the training grounds for Osama bin Laden's terrorists.
Stone number seven, Sapphirus, of Aaron's breastplate (see GLOSSARY) and, as previously mentioned, other ancient references to sapphire are now considered to have referred to lapis lazuli, rather than sapphire.
In some schemes, lapis lazuli is considered the birthstone for December.
SIMULANTS: Along with the distinguishing properties listed in square brackets ([ ]) most simulants for lapis lazuli can be seen with the naked eye or with aid of only a handlens to be virtually single phase materials whereas lapis lazuli can be seen to be made up of more than one mineral. However, one lapis lazuli imitation has recently been found to consist of ground fragments of (Not recorded, but possibly even lazurite) with the metallic-appearing veining made up largely of microscopic flakes of brass within a plastic resin rather than pyrite. (Renfro and Owens, 2010)
Alabaster dyed blue - [texture; lack of pyrite; inferior hardness; presence of concentrations of dye].
Anhydrite dyed blue - [same differences as those given for alabaster].
***Barite and gibbsite powder plus an organic (e.g., polymer) cement (Keeling, 1992). - [Appearance suffices.].
***Barium sulfate and pyrite in a polymer matrix (Koivula, Kammerling and Fritsch, 1992, p.66). - [greater specific gravity (S.G. > ~ 4.48)].
Calcite marble (e.g., Mexican onyx) dyed blue. - [see Carbonate minerals listing.].
California lapis - massive dumortierite quartz, which is an opaque, intense blue to greenish or violet blue material that consists largely of quartz and dumortierite, either as a pigment of or "intergrown" with the quartz. - [superior hardness (H. 7)].
Carbonate minerals (i.e., fine grained rocks or sintered powders of such minerals as calcite, dolomite, and magnesite) dyed. - [Each of these materials effervesces with dilute HCl at room or slightly elevated temperatures whereas only the white portions of some lapis lazuli so-react].
***Ceramic materials of ultra-marine blue color have been fashioned into diversely shaped beads since at least the mid 1970s. See also Wedgwood china listing. - [Appearance suffices.].
Chalcedony stained blue - has been marketed as German lapis or Swiss lapis. - [more homogeneous than lapis lazuli].
Chert stained blue - used the same way as stained chalcedony and jasper; see those listings and also German lapis.
***Cobalt glass (opaque blue) with white cristobalite crystallites comprising irregular zones. - [lower specific gravity].
Coral dyed blue - [texture plus differences listed under Carbonate minerals listing].
Dolomite - see Carbonate minerals.
Dumortierite quartz rock - see California lapis.
***Faience - appropriately colored faience, a glazed ceramic, has been used for "lapis" beads, etc. - [relatively easily distinguished, especially under handlens, since faience is a so-to-speak single phase material].
False lapis - name sometimes given to substitutes that consist largely of the mineral lazulite, blue-dyed chalcedony or jasper. - [if so named, no problem].
Feldspar dyed blue - [superior hardness and dyed appearance].
German lapis - see Jasper....
***Gibbsite and barite powder plus an organic (polymer) cement. - [Appearance suffices.].
***Glass with included pyrite or spangles of native copper. - [Appearance suffices -- e.g., the luster is quite different.].
Howlite dyed blue - [Hardness of howlite (3½) is less than all but certain, sometimes present, minor constituents of lapis lazuli.].
Italian lapis - see Jasper.
Jasper dyed blue - an example is that from Nunkirchen, Germany, which has been referred to as German lapis. Italian lapis is similar. See also Swiss lapis. - [Jasper is more homogeneous than lapis lazuli, although rough material may contain crystal-lined micro cavities; in addition, typical jasper lacks pyrite.].
***Lapis lazuli ware - Wedgwood china, colored and patterned to resemble lapis lazuli. - [Appearance suffices.].
Marble dyed blue - [Hardnesses of chief marble constituents are less than all but minor constituents of lapis lazuli.].
Magnesite dyed blue - some of this material has been marketed as howlite lapis (Koivula, Kammerling and Fritsch, 1993). - [See Carbonate minerals; also superior specific gravity.].
Organic materials stained or dyed - these include bone, ivory, nacre, and even wood. - [Textures,specific gravities, hardnesses, etc. are different from those of lapis lazuli.].
Phlogopite-rich aggregate - an aggregate of phlogopite (potassium magnesium mica), lazurite and ... - [Appearance suffices.].
***Plastics and resins - [inferior specific gravities and do not exhibit the irregular granularity of most lapis lazuli].
Quartzite dyed blue - [superior hardness].
***Reconstructed lapis lazuli - consists largely of barium sulfate (dyed?!) with or without pyrite. - [ See Barium sulfate listing.].
Serpentine stained with ultramarine - this material, apparently originating in India, has been marketed as lapis lazuli with no modifying term preceding it. - [Hardness of serpentine (2½ - 3½) is less than all but minor constituents of lapis lazuli.].
Soapstone, calcite and quartz rock dyed blue. -
Sodalite - [different bluish hue, lower specific gravity]. See SODALITE entry.
***Spinel (i.e., synthetic sintered blue spinel, some with included flecks of gold). - [general appearance and superior hardness].
Swiss lapis - chalcedony or jasper artificially colored blue. From published descriptions, it seems that some of this fairly dark blue jasper may represent natural color, rather than dye. - [Typically is more homogeneous than lapis lazuli and generally lacks pyrite.].
***Synthetic lazurite - two have been produced and marketed by Pierre Gilson - [Much of one of the products is pure blue -- i.e., it lacks the non-blue minerals typical of natural lapis lazuli; the other one contains emplaced pyrite inclusions that do not exhibit the crystal shapes of the typcial pyrite of lapis lazuli.].
Vulpinite (dyed anhydrite). - [see Anhydrite.].
REFERENCES: Covington, 2013; da Cunha, 1989; Hogarth, 1970; Ostwald, 1963; Wyart, Bariand and Filippi, 1981.
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