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Volume 11, pages 334-340, 1926


      LLOYD W. FISHER AND EDWIN K. GEDNEY, Brown University

      A recent survey of the minerals of the state of Rhode Island which are included in the museum collections of the Department of Geology of Brown University and of Roger Williams Park of Providence, together with a careful study in the field by the authors and others have revealed the presence of at least sixty species of minerals from forty-five localities. A brief discussion of the chief mineral localities and occurrences in Providence County1 is here recorded.



Actinolite Fluorite Octahedrite
Albite Galena Opal
Allanite Garnet Orthoclase
Ankerite Glaucophane Ottrelite
Anthophyllite Gold2 Phlogopite
Apatite Goethite Pyrite
Aragonite Graphite Pyrolusite
Arfvedsonite Hematite Pyrrhotite
Augite Hornblende Quartz
Azurite Hortonolite Rhodochrosite
Barite Ilmenite Rhodonite
Beryl Ilvaite Riebeckite
Biotite Jamesonite Rutile
Boltonite Knebelite Scapolite
Bowenite Limonite Scolecite
Calcite Magnetite Serpentine
Chalcopyrite Malachite Siderite
Crocidolite Melanterite Sphalerite
Cryolite Microcline Talc
Cyanite Muscovite Titanite
Dolomite Molybdenite Tourmaline
Enstatite   Tremolite
Epidote   Zoisite




      Fenner's Ledge on Cranston street has been worked in the past for graphite and graphitic anthracite and shows quite a number of the minerals listed from Violet Hill, Manton Avenue. Large veins of fibrous quartz replacing actinolite traverse the exposure.

Fenner's Ledge Actinolite With graphite.
  Graphite Foliated, veined and bedded in shale.
  Hematite Bright red in shale.
  Limonite Yellow and iridescent.
  Melanterite3 Yellow and white, incrusting.
  Ottrelite4   Small lustrous plates in schist.
  Pyrite In shale.
  Quartz  Massive, crystalline. Pseudomorphous after actinolite.



      Fully one-half of the minerals of Providence county are found within the limits of this township. Quartz, epidote and hematite are common while fluorite and galena are more or less abundant.

 Beacon Pole Hill Arsenopyrite Rare.
Crocidolite Blue, fibrous, with smoky quartz.
Quartz    Smoky.  
Copper Mine Hill Actinolite
Azurite Rare. Coatings on chalcopyrite.
Chalcopyrite Massive, with magnetite.
Epidote Veined.
Magnetite Massive, with cumberlandite.
Malachite Botryoidal, with chalcopyrite.
Cumberland Hill  Beryl Green crystals, sparingly, with quartz.
     Village -in quartz veins Biotite Small plates.
Calcite In glacial boulders with sphalerite, siderite and cryolite.
Chalcopyrite With galena and sphalerite.
Chlorite Altering to magnetite and ilmenite.
Cryolite Same as calcite.
Cumberlandite Massive.
Epidote Massive. Some large crystals.
Fluorite Octahedrons. Purple chlorophane.
Galena Cubes, octahedrons, some coated with pyrite, sphalerite, chalcopyrite and fluorite.
Hematite Fine crystals in veins in chlorite.
Hornblende Elongated crystals on quartz.
Ilmenite  Lustrous plates in chlorite schist.
Limonite Coatings on quartz.
Magnetite Small octahedrons.
Malachite Botryoidal. Rare. On chalcopyrite.
Molybdenite In boulders with magnetite.
Phlogopite Crystals near contact with schist.
Pyrite Crystalline. Not common.
Pyroxene Augite crystals in quartz.
Quartz  Rock crystal; Smoky; Milky; Massive; Ferruginous; Sagenitic, with hornblende and tourmaline; Prase.
Siderite In glacial boulders with calcite, etc.
Sphalerite "Black jack," crystalline, with chalcopyrite, fluorite and galena.
Tourmaline5 Schorl in unterminated crystals, and dichroite, rare.
Diamond Hill Barite Rare.
Limonite  Coating quartz.
Quartz Var. Agate; Amethyst; Chalcedony; Chrysoprase; Heliotrope; Jasper; Milky; Onyx; Rock crystal; Sardonyx; Smoky.
Zoisite Dark crystalline with quartz.
Iron Mine Hill Actinolite
Hortonolite Dark crystals.
Ilvaite In veins.
Magnetite Massive in cumberlandite boulders.
Molybdenite  With magnetite.
Pyrolusite With iron ore and in gneiss.
Serpentine Greenish with iron ore.
Talc White and green foliated with iron ore.




      The Harris limestone quarries in this township are rather important because of the abundance of minerals found and these include the beautiful specimens of flattened, yellowish-tinged quartz.

Harris Quarry Calcite Milky crystals, modified scalenohedrons and rhombohedrons; white calcite rhombs; Iceland spar. Limestone with graphite. Graphitic marble.
  Limonite Black and brown.
  Opal Blue coatings on weathered quartz.
  Quartz Flat, tabular crystals, tinged with yellow in veins with calcite.
  Rutile Minute brownish crystals in quartz.
  Scolecite  Minute crystals with calcite.
  Serpentine Var. bowenite in limestone.
  Talc White, pale green, foliated.
Trolley cuts6 Actinolite In schist.
  Bowenite With calcite.
  Calcite Milky, good rhombs, in schist.
  Chalcopyrite Massive in granite pegmatite.
  Goethite  From pyrite.
  Malachite Botryoidal on chalcopyrite.
  Molybdenite Rare. In granite.
  Muscovite Rather large plates in granite.
  Octahedrite White and pale pink crystals accompanying titanite.
  Orthoclase Bright red, pink and rarely white in granite porphyry.
  Pyrite In cubes in granite and schist.
  Quartz Crystalline in veins; blue in contact.
  Rhodonite Massive and crystalline in schist.
  Serpentine With calcite in schist.
  Titanite Black curved prisms in schist and granite.


Centredale Mineral Spring Ave. Calcite Rhombs, in green schist with epidote and quartz.
  Chalcopyrite With epidote and quartz.
  Tremolite White, fibrous.
Smith street - in green schist  Actinolite  
  Calcite Rhombs, cream color.
  Chalcopyrite Auriferous.
  Epidote Massive and granular.
  Magnetite Small octahedrons.
  Pyrite Massive.
  Quartz Crystalline
One mile north Jamesonite Found in small amount in milky quartz dike in granite.


      This is probably one of the best localities in the State to study the effects of contact mineralization and the gradation of iron-magnesium minerals to the more calcic varieties along the contact of the green schist and limestone. Huge masses of steatite are present and in this locality there are numerous pits and cavities in the masses from which the Indians fashioned pots and bowls.

Actinolite Green, bladed in schist-limestone contact.
Ankerite Brownish and black crystals in dolomite and limestone.
Anthophyllite In clove brown crystals near contact.
Calcite Small white crystals in the limestone.
Chlorite In green schist.
Dolomite  Brownish with ankerite and siderite.  
Hematite Sparingly in black crystals.
Hornblende Crystals in green schist.
Limonite Pseudomorphs after pyrite.
Magnetite With siderite.
Pyrite Cubes, octahedrons, and pyritohedrons in steatite.
Siderite In veins and pale brown crystals in dolomite.
Steatite Gray massive.
Talc Foliated, white and green in steatite.
Tremolite White, bladed, in limestone-schist contact.


Violet Hill Manton Avenue Actinolite Green, radiating.
  Ankerite Rhombs in steatite.
  Apatite Yellowish crystals in chlorite schist.
  Asbestus White, in seams in schist.
  Boltonite Sparingly in yellow crystals with talc.
  Calcite Small crystals with talc and quartz.
  Chalcopyrite Massive in limestone with malachite. 
  Chlorite In schist.
  Clinochlore Small plates.
  Dolomite Small transparent, colorless crystals in limestone.
  Epidote Yellowish, elongated crystals with calcite in schist.
  Hematite Black, lamellar, in limestone with chalcopyrite and malachite.
  Hornblende Small black crystals.
  Limonite Pseudomorphs after pyrite.
  Magnetite Small octahedrons in amphibolite.
  Malachite Botryoidal on chalcopyrite.
  Orthoclase Pink with epidote.
  Pyrite In cubes in limestone and schist.
  Pyroxene Small crystals.
  Pyrrhotite In small crystals in schist and steatite.
  Quartz Chiefly as vein material.
  Rhodochrosite Same as rhodonite.
  Rhodonite  Pink, with epidote and calcite.
  Serpentine Light and dark yellowish green with slickensided surfaces.
  Steatite Light gray.
  Talc White and pale green foliated with calcite.
  Tremolite White and fibrous.



      1 A paper is being prepared by the authors on the remaining localities.

      2 In chalcopyrite. With quartz in schist.

      3 Occurring with the melanterite but not directly in contact with it are two different iron sulphates, one almost pure white and the other of a cream color. Both show considerable amounts of ferric iron and magnesium is noted in the pure white one.

      4 A study of ottrelite, its crystallography, chemistry and origin is being made by the authors with Prof. C. W. Brown and will be presented in a later paper.

      5 Schorl in quartz at contact with gneiss, dichroite at contact with green schist.

      6 These cuts are located along the right of way of the Providence to Woonsocket Electric Railway chiefly between Miner's Crossing and Lime Rock Station (Wilbur Road).

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