Lapis Lazuli, Spiny Oyster, and Beyond

Lapis lazuli holds the distinction of being one of the longest continuously traded gemstones in human history. The primary source — the Sar-e-Sang mines in the Badakhshan province of northeastern Afghanistan — has been in operation for over 6,000 years, supplying the ancient Egyptian, Mesopotamian, Greek, and Roman civilizations with the intensely blue stone that was ground into the pigment ultramarine, used to decorate the funeral mask of Tutankhamun, and traded across the full breadth of the ancient world.

The mineral composition of lapis lazuli is complex. It is not a single mineral but a rock composed primarily of lazurite (the blue mineral, a sodium calcium aluminosilicate sulfide), with variable quantities of calcite (white), pyrite (metallic gold), and sodalite (blue). The finest lapis — designated 'AAA' or 'Afghan grade' in the trade — displays a deep, saturated violet-blue color with minimal calcite and evenly distributed flecks of golden pyrite that catch light like stars in a night sky. The pyrite inclusions, far from being imperfections, are considered a hallmark of authenticity and a contributor to the stone's distinctive beauty.

Lapis lazuli entered the Native American jewelry vocabulary primarily in the twentieth century, as improved international trade networks made the material more readily available to Southwestern lapidaries and jewelers. Zuni inlay artists adopted lapis enthusiastically, using its deep blue as a counterpoint to turquoise's lighter hue in multi-stone compositions. The contrast between lapis and turquoise — both blue, but occupying different registers of the color spectrum — creates sophisticated chromatic relationships that have become a signature element of contemporary Zuni channel and mosaic inlay.

Navajo silversmiths use lapis primarily as a statement stone, setting large cabochons in silver bezels where the stone's deep blue provides a dramatic alternative to turquoise. The combination of lapis with silver creates a color relationship — cool blue against warm gray-white metal — that reads differently from turquoise and silver, giving the jeweler an expanded expressive range.

Grading lapis lazuli for jewelry use follows established conventions. Color saturation is the primary criterion: deep, uniform violet-blue commands the highest prices, while pale or greenish-blue (indicating high sodalite or calcite content) grades lower. Pyrite distribution affects value — evenly scattered small pyrite crystals are desirable, while large pyrite masses or concentrations are considered less attractive. Calcite content should be minimal; large white calcite patches reduce both color saturation and structural integrity. The best lapis takes a glassy polish and exhibits good hardness (5.5 on the Mohs scale), suitable for all jewelry applications.

Current market prices for gem-grade Afghan lapis range from $3-8 per carat for good commercial material to $50-100 per carat for exceptional AAA-grade stones with perfect color and pyrite distribution. Chilean lapis, from deposits near Santiago, provides an alternative source but typically exhibits paler color with more calcite than the Afghan standard. Russian lapis from the Lake Baikal region of Siberia produces high-quality material but is available in limited quantities on the Western market.

While the preceding article on coral and shell introduced spiny oyster shell in its cultural and historical context, this section examines the detailed grading criteria that determine value in the contemporary market. Spondylus princeps produces shell material in a color range that spans from deep red-orange through bright tangerine, golden amber, and — most prized by many contemporary collectors — vivid purple.

The grading hierarchy for spiny oyster has evolved significantly over the past two decades. Historically, the red-orange material closest in color to Mediterranean coral commanded the highest prices, as it served as a more affordable alternative in coral-style designs. Market preferences have since diversified, and purple spiny oyster has emerged as the most sought-after color variety, with gem-grade purple specimens trading at $15-40 per carat — prices that approach or exceed those of many semi-precious gemstones.

Purple spiny oyster derives its color from organic pigments deposited during shell growth, with the most saturated purple occurring in shells from deeper waters where specific environmental conditions favor purple pigmentation. The purple ranges from lavender through medium violet to deep royal purple, with the most saturated, uniform specimens grading highest. Purple spiny oyster has become particularly associated with Navajo jewelry, where large purple cabochons set in elaborately stamped silver create a color combination — purple against silver-white — that is distinctive and immediately recognizable.

Orange spiny oyster, the most abundant color variety, is graded primarily on color saturation and uniformity. The brightest, most vivid orange — sometimes called 'flame' orange in the trade — commands premiums above paler or more muted specimens. Surface quality matters: the finest spiny oyster shell takes a high polish with visible chatoyancy (a silky sheen caused by the material's layered microstructure), while lower grades show surface pitting, chalky areas, or dull spots that reduce visual impact.

The thickness of the color-bearing layer is a practical consideration in lapidary work. Spiny oyster color is not uniform throughout the shell's cross-section — the vivid exterior color layer may be only a few millimeters thick, with paler or white material beneath. Skilled lapidaries orient their cuts to maximize the color-bearing layer's presence on the finished cabochon's display face, but thin color layers limit the maximum depth of cabochon that can be cut without exposing the paler substrate. This constraint makes thick-shelled specimens with deep color penetration particularly valuable to lapidaries.

Authentication involves distinguishing genuine Spondylus shell from dyed substitutes. Common imitations include dyed magnesite (a white mineral easily tinted to approximate spiny oyster colors), dyed howlite, and reconstituted shell composite. Under magnification, genuine spiny oyster shows characteristic growth lines and a fibrous lamellar structure absent in dyed mineral substitutes. The acetone swab test can detect surface dye on imitations, though some sophisticated dyeing processes penetrate deeply enough to resist surface testing.

The expansion of the Native American jewelry palette beyond traditional turquoise, coral, and shell accelerated in the latter decades of the twentieth century as lapidaries and jewelers gained access to newly discovered or newly popularized mineral species. Several of these secondary stones have achieved significant market presence and collector following.

Gaspeite, a bright apple-green nickel carbonate mineral first described from the Gaspe Peninsula of Quebec, entered the Southwestern jewelry market in the 1990s through material sourced primarily from Australian nickel mines. Its vivid green — brighter and more yellow-toned than most turquoise — provides a striking color accent in multi-stone inlay designs. Gaspeite's relative softness (4.5-5 on the Mohs scale) requires careful handling but does not preclude jewelry use in protected settings. The material remains uncommon enough that gaspeite-bearing pieces carry a novelty premium, particularly in the Japanese and European markets where the stone has developed an enthusiastic collector following.

Sugilite, a purple cyclosilicate mineral discovered in 1944 and named for the Japanese petrologist Ken-ichi Sugi, achieved commercial significance following the discovery of gem-quality deposits at the Wessels Mine in South Africa's Kalahari manganese field. Gem-grade sugilite displays a saturated purple to violet-purple color that has no close equivalent among traditional Southwestern jewelry materials. Zuni inlay artists adopted sugilite eagerly, using its purple as a color complement to turquoise's blue and coral's red in compositions that span the full chromatic circle. High-grade sugilite — intensely colored, translucent, and free of matrix — is now genuinely rare, with the Wessels Mine deposits largely depleted. Current prices for gem-grade sugilite range from $15-50 per carat, with exceptional material exceeding $100 per carat.

Charoite, a purple silicate mineral found exclusively in the Chara River area of Yakutia, Siberia, produces material with a distinctive swirling, chatoyant texture that has no parallel in the mineral world. The stone's lavender to deep purple color, combined with its unique pattern of interlocking fibrous crystals, creates a visual effect that reads as dynamic and organic — qualities that appeal to jewelers seeking materials with inherent visual complexity. Charoite's single-source origin from a politically complicated region has created supply uncertainties that support its collector value.

Variscite, a green hydrated aluminum phosphate mineralogically related to turquoise, produces material ranging from pale mint green to deep emerald green. The finest variscite, from deposits in Utah (the Lucin and Clay Canyon mines), Nevada, and Australia, rivals the best green turquoise in color saturation while offering a distinct aesthetic — smoother, more uniform, and more translucent than turquoise. Some lapidaries and dealers have observed that high-grade variscite is becoming increasingly difficult to source, suggesting that collector attention may intensify as availability diminishes.

The incorporation of non-traditional materials into Native American jewelry reflects both market evolution and artistic ambition. Contemporary jewelers, particularly those working in the channel inlay tradition pioneered by Zuni artisans, seek materials that expand their chromatic palette beyond the red-blue-white-black framework of traditional coral-turquoise-shell-jet compositions. The result is a material vocabulary that now encompasses dozens of stone species, creating possibilities for color and pattern complexity that previous generations of jewelers could not achieve.

This expansion has not occurred without controversy within indigenous jewelry communities. Traditionalists argue that the proliferation of non-indigenous materials dilutes the cultural specificity that distinguishes Native American jewelry from other world jewelry traditions. The sacred and cosmological associations of turquoise, shell, coral, and jet — materials embedded in creation stories and ceremonial practice for centuries — cannot transfer to gaspeite, sugilite, or charoite, which have no established place in indigenous spiritual frameworks.

Proponents of material expansion counter that Native American jewelry has always been an evolving tradition that absorbs new materials and techniques. Silver itself was adopted from Spanish and Mexican metalworking traditions in the nineteenth century. Mediterranean coral arrived through colonial trade networks. Even turquoise varieties have shifted over time as new mines have opened and old ones closed. From this perspective, the adoption of gaspeite or sugilite represents the latest chapter in a centuries-long tradition of creative adaptation rather than a departure from authentic practice.

The market ultimately reflects both perspectives. Pieces crafted exclusively from traditional materials — turquoise, coral, shell, jet, and silver — maintain strong commercial viability, particularly among collectors who value cultural continuity. Meanwhile, pieces incorporating contemporary stone selections find enthusiastic buyers among collectors who appreciate innovation within the Native American jewelry tradition. Both approaches coexist productively, expanding the total market rather than competing for fixed demand.

For collectors navigating this expanded material landscape, education remains the primary tool. Understanding the geological origin, cultural context, and grading criteria for each material enables informed purchasing decisions. A collector who knows that the deep purple stone in a bracelet is sugilite from South Africa — a genuinely rare mineral — will value it differently than one who merely sees 'a pretty purple rock.' The depth of appreciation that knowledge enables is, ultimately, what transforms a purchase into a collection and a buyer into a connoisseur.