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Bordonaro Quarry, Portland, Middlesex Co., Connecticut, USAi
Regional Level Types
Bordonaro QuarryQuarry
Portland- not defined -
Middlesex Co.County

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Looking away from the upper trench down the dumps.

Bordonaro Quarry, Portland, Middlesex Co., Connecticut, USA
Looking toward a large trench in the upper dump.

Bordonaro Quarry, Portland, Middlesex Co., Connecticut, USA
Latitude & Longitude (WGS84):
41° 37' 20'' North , 72° 35' 47'' West
Latitude & Longitude (decimal):
Locality type:
Nearest Settlements:
Cromwell13,750 (2017)5.1km
Portland5,862 (2017)6.6km
Lake Pocotopaug3,436 (2017)7.6km
Middletown46,756 (2017)8.0km
Glastonbury Center7,387 (2017)8.8km

Quarry and prospects in small granite pegmatite dike noted mostly for a relative abundance of beryl.

According to Cameron (1954) and Boos (1949), the property was owned in 1943 by Sam Bordonaro, of Portland. In 1929 Joseph Carini, worked one of the pegmatites on the property and recovered a few tons of feldspar, beryl and scrap mica. In 1935 Bordonaro mined feldspar and sold some run-of-the-mine mica to the Huse-Liberty Co., in Middletown, Conn.. The Bordonaro pegmatite strikes nearly N. - S. and dips west 25°-55°. The average dip is about 45°. The south half of the Bordonaro dike was mined in two sections. The first quarry was about 55 feet long and the second about 38 feet long. The two openings range from 1 foot to 10 feet in depth and for most of their length expose the pegmatite from wall to wall. A small prospect cut 30 feet south of the quarry exposes pegmatite.

The south section has a striking zonal structure. It consists of the following units, in order from the walls inward:

1. Border zone, plagioclase-quartz-perthite pegmatite, 1 to 3 inches thick. Composed of fine- to medium-grained quartz and albite plagioclase, with subordinate muscovite and microcline perthite, and accessory garnet and unevenly distributed beryl. The beryl crystals are ½ to 1½ inches in diameter and as much as 3 inches long.
2. Perthite-quartz zone, 3 inches to 1 foot thick. Composed of coarse perthite and quartz, with subordinate muscovite and albite plagioclase. The microcline perthite crystals are euhedral against the quartz and also against quartz of the core described below. The zone is absent along part of the footwall.
3. Quartz core, 6 inches to 1½ feet thick. Consists of coarse, massive quartz.

The north section of the dike consists of the following zones:

1. Border zone, ½ inch to 2 inches thick, similar to the border zone of the south section. The zone is absent at a few places along the hanging wall.
2. Wall zone, plagioclase-quartz-perthite pegmatite, 1 to 8 inches thick. Composed of quartz and albite plagioclase, with subordinate microcline perthite and muscovite and accessory beryl, tourmaline, and garnet. The zone is less than 4 inches thick in most places and is discontinuous. The mica books are ½ inch to 6 inches broad, and ¼ inch to 2 inches thick. The mica is green, clear, and hard, but most of it is ruled, reeved, cross-fractured, and tangled. Inclusions of albite, quartz, tourmaline, and garnet are present in some books. Few books would yield even small sheet mica.
3. Perthite-quartz zone, 6 inches to 5 feet thick. This zone varies markedly from place to place in mineral proportions, but in general consists of quartz and coarse microcline perthite, with subordinate medium-grained albite plagioclase and muscovite, and accessory beryl and garnet. Perthite forms anhedral to subhedral crystals a few inches to 3 feet in diameter. Some of the crystals are intergrown with quartz. Light green to blue-green subhedral beryl crystals as much as 6 inches long and 2.5 inches in diameter are scattered unevenly through the zone. Some of the crystals seem to be pure and some are intergrown with or include quartz and feldspars or are veined by quartz and albite.

The other pegmatites exposed on the property are medium- to coarse-grained and consist essentially of quartz, albite plagioclase, microcline perthite, and muscovite in various proportions. Apart from thin border zones, they appear unzoned.

Regions containing this locality

North America PlateTectonic Plate

Select Mineral List Type

Standard Detailed Strunz Dana Chemical Elements

Mineral List

10 valid minerals.

Detailed Mineral List:

Formula: Na(AlSi3O8)
Colour: white
Fluorescence: none
Description: Mostly massive, minor vuggy zones with micro-crystals or albite and quartz.
Reference: USGS Prof Paper 255, Harold Moritz collection
Formula: Fe2+3Al2(SiO4)3
Habit: dodecahedral
Colour: burgundy
Description: crystals typically <5 mm.
Reference: Van King
Formula: Be3Al2(Si6O18)
Habit: subhedral, hexagonal prisms with pinacoid terminations
Colour: Light green to blue-green
Description: Light green to blue-green subhedral beryl crystals as much as 6 inches long and 2.5 inches in diameter are scattered unevenly through the perthite-quartz zone. Some of the crystals seem to be pure and some are intergrown with or include quartz and feldspars or are veined by quartz and albite.
Reference: USGS Prof Paper 255
Formula: Fe2+Nb2O6
Habit: bar-shaped to tabular
Colour: black
Description: Identified partly by SG of an isolated crystal (6.35). Crystals loose in dump are up to 45mm long.
Reference: Harold Moritz collection
Formula: Ca5(PO4)3F
Reference: Schooner, Richard. (1958)
Formula: K(AlSi3O8)
Description: Microcline perthite forms anhedral to subhedral crystals a few inches to 3 feet in diameter.
Reference: Van King, Cameron (1954), Boos (1949)
Formula: KAl2(AlSi3O10)(OH)2
Colour: pale green
Description: The mica books are ½ inch to 6 inches broad, and ¼ inch to 2 inches thick. The mica is green, clear, and hard, but most of it is ruled, reeved, cross-fractured, and tangled.
Reference: Brookins, D.G., Fairbairn, H.W., Hurley, P.M., and Pinson, W.H. (1969): Contributions to Mineralogy and Petrology 22, 157-168.; USGS Prof Paper 255
Formula: SiO2
Habit: vast majority is massive, small crystals in vuggy albite are elongated prismatic
Colour: massive material is smoky, pocket crystals are colorless to pale blue-gray.
Description: Very elongated crystals in vuggy albite can reach 58 mm, with frosty surface and a blue-gray tint.
Reference: USGS Prof Paper 255
Formula: Na(Fe2+3)Al6(Si6O18)(BO3)3(OH)3(OH)
Habit: elongated prismatic
Colour: Black
Description: Mostly as subhedral crystals forming layers in the metamorphic rock along the contact with the pegmatite.
Reference: USGS Prof Paper 255
Formula: UO2
Habit: crudely octahedral
Colour: black
Description: very small irregular masses are embedded in fluorapatite, isolated crystals in pegmatite matrix with halos of secondary minerals.
Reference: Schooner, Richard. (1958)

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
Group 8 - Phosphates, Arsenates and Vanadates
Group 9 - Silicates

List of minerals arranged by Dana 8th Edition classification

Group 51 - NESOSILICATES Insular SiO4 Groups Only
Insular SiO4 Groups Only with cations in [6] and >[6] coordination
Group 61 - CYCLOSILICATES Six-Membered Rings
Six-Membered Rings with [Si6O18] rings; possible (OH) and Al substitution
Six-Membered Rings with borate groups
Group 71 - PHYLLOSILICATES Sheets of Six-Membered Rings
Sheets of 6-membered rings with 2:1 layers
Group 75 - TECTOSILICATES Si Tetrahedral Frameworks
Si Tetrahedral Frameworks - SiO2 with [4] coordinated Si
Group 76 - TECTOSILICATES Al-Si Framework
Al-Si Framework with Al-Si frameworks

List of minerals for each chemical element

H MuscoviteKAl2(AlSi3O10)(OH)2
H SchorlNa(Fe32+)Al6(Si6O18)(BO3)3(OH)3(OH)
Be BerylBe3Al2(Si6O18)
B SchorlNa(Fe32+)Al6(Si6O18)(BO3)3(OH)3(OH)
O Columbite-(Fe)Fe2+Nb2O6
O MuscoviteKAl2(AlSi3O10)(OH)2
O MicroclineK(AlSi3O8)
O AlmandineFe32+Al2(SiO4)3
O BerylBe3Al2(Si6O18)
O SchorlNa(Fe32+)Al6(Si6O18)(BO3)3(OH)3(OH)
O UraniniteUO2
O FluorapatiteCa5(PO4)3F
O QuartzSiO2
O AlbiteNa(AlSi3O8)
F FluorapatiteCa5(PO4)3F
Na SchorlNa(Fe32+)Al6(Si6O18)(BO3)3(OH)3(OH)
Na AlbiteNa(AlSi3O8)
Al MuscoviteKAl2(AlSi3O10)(OH)2
Al MicroclineK(AlSi3O8)
Al AlmandineFe32+Al2(SiO4)3
Al BerylBe3Al2(Si6O18)
Al SchorlNa(Fe32+)Al6(Si6O18)(BO3)3(OH)3(OH)
Al AlbiteNa(AlSi3O8)
Si MuscoviteKAl2(AlSi3O10)(OH)2
Si MicroclineK(AlSi3O8)
Si AlmandineFe32+Al2(SiO4)3
Si BerylBe3Al2(Si6O18)
Si SchorlNa(Fe32+)Al6(Si6O18)(BO3)3(OH)3(OH)
Si QuartzSiO2
Si AlbiteNa(AlSi3O8)
P FluorapatiteCa5(PO4)3F
K MuscoviteKAl2(AlSi3O10)(OH)2
K MicroclineK(AlSi3O8)
Ca FluorapatiteCa5(PO4)3F
Fe Columbite-(Fe)Fe2+Nb2O6
Fe AlmandineFe32+Al2(SiO4)3
Fe SchorlNa(Fe32+)Al6(Si6O18)(BO3)3(OH)3(OH)
Nb Columbite-(Fe)Fe2+Nb2O6
U UraniniteUO2


Sort by

Year (asc) Year (desc) Author (A-Z) Author (Z-A)
Cameron, E. N., and Shainin, V. E. (1947): The Beryl Resources of Connecticut. Econ. Geology, v. 42, p. 353-367.
Boos, M. F., E. E. Maillot and. McHenry Mosier. (1949): Investigation of Portland Beryl-Mica District, Middlesex County, Conn. United States Bureau of Mines, Report of Investigations R.I. 4425.
Cameron, Eugene N., Larrabee David M., McNair, Andrew H., Page, James T., Stewart, Glenn W., and Shainin, Vincent E. (1954): Pegmatite Investigations 1942-45 New England; USGS Professional Paper 255.
Stugard, Frederick, Jr. (1958): Pegmatites of the Middletown Area, Connecticut. U. S. Geol. Survey Bull. 1042-Q.
Schooner, Richard. (1958): The Mineralogy of the Portland-East Hampton-Middletown-Haddam Area in Connecticut (With a few notes on Glastonbury and Marlborough).
Schooner, Richard. (1961): The Mineralogy of Connecticut.
Brookins, D.G., Fairbairn, H.W., Hurley, P.M., and Pinson, W.H. (1969): A Rb-Sr Geochronologic Study of the Pegmatites of the Middletown Area, Connecticut). Contributions to Mineralogy and Petrology 22, 157-168.

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