Triplite from
Anderson No. 1 Mica Mine (Swanson Mine; Swanson Lithia Mine; Old Lithia Mine; Chatham Lithia Mine), East Hampton (Chatham), Middlesex County, Connecticut, USA
| Locality type: | Mine | |
| Classification | ||
|---|---|---|
| Species: | Triplite | |
| Formula: | Mn22+(PO4)F | |
| Comments: | As irregular masses, commonly in bunches intergrown with blue elbaite and dark purple lepidolite and hosted by cleavelandite/elbaite/quartz. Tan alteration rind around the edges is probably hydroxylapatite (see below) and Schooner reports finding hureaulite. These minerals are characteristic of alteration from primary lithiophilite but none has ever been reported, so it is difficult to say if the triplite is primary. Masses of garnet may appear similar, but are harder and show a network of rhombic etch patterns on fracture surfaces. Descriptions from the literature are below: Shannon (1920) - "bunches and masses up to several inches across of a flesh red to brownish red material resembling massive garnet, which upon analysis proves to be triplite...In places the triplite has oxidized to a black manganese oxide, which stains the cleavelandite." Foye (1922) - "intimately intergrown with a dark blue, massive tourmaline". Schooner (1958) – "Large masses, up to a foot square, occurred in a mixture of that mineral and cleavelandite. The author was fortunate in securing a large specimen of completely fresh material from a weathered boulder on the oldest dump. Most examples show what are probably crude crystals, bordered with blue tourmaline. Much of the triplite is altered to a cellular tan mineral which has not been thoroughly identified. One piece, evidently from deep in the pegmatite, has undergone a more complex alteration to a foliated dull green substance…negatively identified as not being dickinsonite. Such material could easily be confused with chloritized garnet. Indeed, the fresh triplite resembles massive garnet; its comparative softness and its cleavages should distinguish it. Mary E. Mrose x-rayed this triplite for the author and found it to give a characteristic pattern. E. V. Shannon, who originally described the occurrence in 1920, gave the following analysis: calcium oxide 3.18, magnesium oxide 0.58, iron oxide 4.95, manganese oxide 52.40, phosphorous oxide 32.81, fluorine 9.09, water 0.35, and remainder 1.17. The specific gravity of the sample was 3.58." Schooner (1961) - "Reddish-brown cleavages, bordered with blue tourmaline, definitely identified as such, were apparently quite common in the original lepidolite pit, where that mineral, together with quartz and cleavelandite, occurred as coarse intergrowths. The author found a solid mass, over six inches across, in the old dump there; some of the triplite bodies must easily have been a foot in diameter. In many cases, the triplite is partially or completely altered to a granular yellow or tan mineral; x-ray study proves this to be apatite, of a surprisingly normal kind. This work was done by Peacor." | |
| Habit: | massive | |
| Colour: | reddish to maroon | |
| Abundance at site: | Common | |
| Confirmation | ||
| Validity: | Confirmed | |
| Confirmation Methods: | XRD | |
| Associated Minerals Based on Photo Data: | ||
| Lepidolite | ⓘ5 photos of Triplite associated with Lepidolite at this locality. | |
| Elbaite | ⓘ3 photos of Triplite associated with Elbaite at this locality. | |
| Cleavelandite | ⓘ3 photos of Triplite associated with Cleavelandite at this locality. | |
| Albite | ⓘ1 photo of Triplite associated with Albite at this locality. | |
| Muscovite | ⓘ1 photo of Triplite associated with Muscovite at this locality. | |
| Data | ||
| Mineral Data: | Click here to view Triplite data | |
| Locality Data: | Click here to view Anderson No. 1 Mica Mine (Swanson Mine; Swanson Lithia Mine; Old Lithia Mine; Chatham Lithia Mine), East Hampton (Chatham), Middlesex County, Connecticut, USA | |
| Photo Gallery | View Gallery (5 photos) | |
| Data Identifiers | ||
| Mindat Occurrence Record ID: | 37796 | |
| Long-form Identifier: | 1:3:37796:6 | |
| GUID (UUID V4): | d119b689-6830-4b58-9f6f-751408414433 | |
| Nearest other occurrences of Triplite | ||
| 10.2km (6.4 miles) | ⓘStrickland Quarry, Strickland pegmatite, Collins Hill, Portland, Middlesex County, Connecticut, USA | |
| 81.4km (50.6 miles) | ⓘFillow Quarry (Branchville Quarry; Branchville Mica Mine; Smith Mine), Branchville, Redding (Reading), Fairfield County, Connecticut, USA | |
| References | ||
Anderson No. 1 Mica Mine, East Hampton, Middlesex County, Connecticut, USA