Papagoite cabochon, Ajo, Arizona. © 49erMinerals. Used with permission.
Cerulean blue papagoite crystals are too small for faceting. However, massive material mixed with quartz can be cabbed, while quartz crystals with papagoite inclusions make striking specimens for collectors.
| Data | Value |
|---|---|
| Name | Papagoite |
| Colors | Cerulean blue. |
| Hardness | 5-5.5; may be approximately 7 if silicified. |
| Cleavage | Distinct on crystals; not observed on microcrystalline material. |
| Formula | CaCuAlSi2O6(OH)3 |
| Etymology | Named after the Papago Native American tribe, now known as Tohono O’odham. |
| Occurrence | In narrow veinlets in altered granodiorite porphyry; as inclusions in quartz crystals. |
| Crystallography | Monoclinic; crystals tiny, flattened; usually microcrystalline coatings and aggregates, sometimes mixed with quartz. |
| Refractive Index | 1.607-1.672 |
| Birefringence | 0.065 |
| Luminescence | None. |
| Luminescence Present | No |
| Absorption Spectrum | Bands centered at 4480, 5150, and 5550. |
| Pleochroism | Colorless to very pale greenish blue/blue/deep greenish blue. |
| Optics | a = 1.607; β = 1.641; γ = 1.672. Biaxial (-). |
| Optic Sign | Biaxial - |
| Luster | Vitreous. |
| Specific Gravity | 3.25 if pure; may be lower (for example, 2.42 on Arizona material) if mixed with quartz. |
| Transparency | Crystals translucent to transparent. Massive material and cabochons are translucent to opaque. |
Deep blue microcrystalline papagoite, 5.4 x 3.0 x 1.2 cm, New Cornelia Mine, Ajo, Pima County, Arizona. © Rob Lavinsky, www.iRocks.com. Used with permission.
Papagoite was originally found as tiny crystals associated with blueish green ajoite in Ajo, Pima County, Arizona. This microcrystalline material isn’t cuttable. However, massive papagoite found mixed with quartz has greater hardness and wearability. It can also take a high polish, which makes it suitable for cabbing. These opaque to translucent cabs can have a vitreous luster.
In South Africa, papagoites can occur as inclusions within quartz crystals.
Quartz with included papagoite (Transvaal, South Africa). Photo by James St. John. Licensed under CC By 2.0.
Under magnification, you can see a regular interlocking structure in massive papagoite/quartz. You may also find tiny metallic copper crystal inclusions. This type of papagoite may look like more well-known chrysocolla or turquoise gems.
Papagoites leave a light blue streak. Please note that streak testing can destroy your specimen. Never perform this test on a finished gem and only do it as a last resort to identify rough.
No known synthetics.
No known treatments.
Arizona and South Africa are the principal producers of this rare gem material. Other sources include Namibia and Slovakia.
Papagoite crystals, 5.9 x 3.3 x 2.1 cm, Sindair Mine, South Central Namibia. © Rob Lavinsky, www.iRocks.com. Used with permission.
Lapidaries can cut cabs up to several inches in length from the massive material.
Clean microcrystalline specimens only with a soft brush, mild detergent, and warm water. Durable cabochons cut from massive material have no special care requirements. For more care recommendations, consult our gemstone jewelry cleaning guide.
Papagoite cabochons and rough. © 49erMinerals. Used with permission.
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