Overview

Indicolite is the blue variety of tourmaline, most commonly an elbaite. Its most desirable hues range from saturated royal to cobalt and teal blue; paler sky-blue to blue-green stones are also collected, especially when lustrous and transparent. Like all tourmalines, indicolite forms elongated, striated trigonal prisms, often with flat or pyramidal terminations and striking color zoning. Because blue is comparatively rare in the tourmaline spectrum, fine indicolite is a trophy color, particularly in crystals with strong saturation that still show good light transmission.

Pleochroism is pronounced: viewed down the c-axis, colors can appear deeper (even inky), while across the a–b axes they lighten and “open.” Specimens often display best when oriented to show the brighter axis and with modest backlighting to bring out internal glow. Classic associations include snow-white cleavelandite (albite), quartz (rock crystal or smoky), and lilac lepidolite—combinations that heighten the blue visually. Collectors seek both elegant single prisms and balanced matrix clusters. Prices span from modest for small bluish-green crystals to very high for saturated, gemmy blues or rare copper-bearing “Paraíba-type” blues in crystal form.

Popularity

Blue tourmaline has long captivated collectors because truly fine blue is markedly scarcer than green or pink. Historic highlights include California’s 1972 Tourmaline Queen “blue cap” pocket, Afghan/Nuristan bicolors with vivid blue tips in the 1980s–1990s, and a sequence of Brazilian finds from the Cruzeiro and Pederneira mines that yielded transparent blue prisms on dramatic matrix. In the 2000s–2010s, Mozambique and Brazil produced copper-bearing, neon teal-blue elbaites—legendary as gems and occasionally preserved as small but dazzling crystals.

Indicolite’s enduring appeal lies in the color challenge: finding saturated blue without being too dark or too green, in crystals that are sharp, lustrous, and preferably on contrasting matrix. Even thumbnail crystals of superb hue can be showstoppers, and collectors often upgrade repeatedly as their eye for color and pleochroism refines.

Top Collecting Localities

Pederneira Mine, Brazil

Minas Gerais’ Pederneira Mine is famed for sculptural, multi-crystal clusters featuring vivid blues and blue-greens, frequently with sharp zoning and “cap” color changes. Albite (cleavelandite), quartz, and lepidolite provide pristine white or lilac contrast, making the blue tourmalines pop. Many pockets yielded slender, lustrous prisms with glassy terminations; the finest show rich medium to deep blues that remain luminous in ambient light. Due to pocket stress, repairs are common; un-repaired matrix pieces with strong color are coveted.

Pala Mining District, San Diego, USA

Pala is an American classic. While famed for pinks and the legendary “blue cap” pocket (indigo caps atop pink bodies) from the Tourmaline Queen, the district also produced true blue to blue-green crystals. The best display with snowy albite or mica-rich matrix, and a few rare matrix clusters are significant historic pieces. California indicolite combines provenance with beauty—top examples are scarce and keenly sought.

Collector’s Guide

Evaluating Specimen Quality

• Color:

  • Aim for saturated, bright blue that remains lively in room light. The sweet spot is medium to medium-dark royal or cobalt blue—dark enough to be rich, but not so dark it reads black.
  • Pleochroism is strong. Viewed along the length (c-axis), indicolite may look darker; across the prism it often appears brighter. Favor display orientations that show the best hue.
  • Teal/blue-green tones can still be excellent if vivid; copper-bearing pieces often show an unmistakable “neon” teal.
  • Dramatic zoning (e.g., blue caps or blue sections within multicolor crystals) can enhance value when attractive on display.

• Clarity & Luster:

  • High clarity, especially in the upper half and termination, gives that coveted inner glow. Turbid or heavily cracked crystals look dull unless color is exceptional.
  • Fresh, glassy prism faces and mirror-bright terminations elevate a piece. Natural striations are normal and should still gleam under light.

• Crystal Form:

  • Well-proportioned, straight prisms with complete terminations are preferred. Classic habits include flat pinacoid tips or steep pyramids; both can be aesthetic if sharp.
  • Matrix adds value when well-composed: white cleavelandite, smoky or rock crystal quartz, and lilac lepidolite provide superb contrast to blue.
  • Clusters should feature distinct, undamaged terminations and a pleasing arrangement—height variation and slight divergence create dynamism.

• Condition:

  • Tip dings and edge nicks are common detractions—inspect ridge lines and terminations closely. A small, unobtrusive nick may be acceptable on an otherwise superior piece.
  • Repairs are common in tourmaline; a single, well-executed repair is often acceptable for significant specimens. Unrepaired pieces command a premium.

• Aesthetics:

  • Seek balance, contrast, and a strong primary display angle. Blue on white matrix is a proven recipe; selective backlighting can amplify color without relying on it fully.

Detecting Repairs or Treatments

• Repairs and Reattachments:

  • Look for straight glue seams, misaligned striations, or shiny epoxy films at joins or where crystals meet matrix. Some epoxies fluoresce under longwave UV.
  • Multiple or obvious repairs should lower price; good dealers disclose repair counts.

• Polishing:

  • Polished terminations can appear “too perfect,” mirror-like, and lack natural growth hillocks or minute features. Polishing should be disclosed and generally lowers desirability.

• Treatments:

  • Heat or irradiation can modify tourmaline colors; these are far more common for cut gems than for preserved crystals. Copper-bearing blues are sometimes heated in the gem market; as intact crystals, treatment is less frequent but possible.
  • Irradiated colors may be less stable to prolonged UV; when in doubt, avoid long sun exposure.

• Fakes:

  • Fully synthetic blue tourmaline crystals are rare in the specimen market. Beware glass or assembled composites—absence of natural striations, rounded bubbles (glass), or odd matrix interfaces are red flags.

Care and Storage

• Handling:

  • Tourmaline is hard but brittle. Support matrix pieces with two hands; avoid pressure on slender prisms and terminations.

• Light and Display:

  • Normal cabinet LEDs are ideal. Avoid months of direct sunlight, especially for potentially irradiated pieces. Use modest backlighting to reveal color while confirming the specimen still looks good in ambient light.
  • Because of pleochroism, rotate a new acquisition to find the orientation with the brightest blue.

• Temperature:

  • Keep away from heat sources and avoid rapid temperature swings; thermal shock can induce cracks, and excessive heat can alter color.

• Cleaning:

  • Dust with a soft brush. For grime, use lukewarm water with a drop of mild dish soap and a very soft brush; rinse and air-dry.
  • Avoid ultrasonic and steam cleaners. Use chemicals cautiously—many matrices (calcite, micas) are sensitive. Test stain removers on inconspicuous areas first.

• Storage:

  • Pad individual specimens in boxes or drawers; don’t let harder pieces rub against softer species and vice versa. Secure display pieces with mineral tack or stands, especially in vibration-prone settings.
  • Label provenance—locality is a significant part of indicolite value (e.g., Pederneira vs. Paprok vs. Paraíba/Mozambique copper-bearing blue).

By focusing on saturated but bright blue color, sharp form, clean terminations, and appealing matrix contrast, collectors can assemble a compelling suite of indicolite—from classic Brazilian and Afghan crystals to the rare neon cuprian blues that helped define a modern era of tourmaline collecting.