Volume 7, pages 4-12, 1922

     Southward along the state road from Glastonbury there are a number of quarry openings. The only one which has produced rare minerals is the Hale or Andrews quarry (Locality 2), situated just south of a small stream at an elevation of 55 meters (180 feet) approximately. The quarry is no longer worked, but in its day it was one of the best in the region. Large, well formed monazite crystals (2 to 3 cm. in diameter) were found here, and are not known elsewhere in the district. Other minerals were molybdenite, sphalerite, rose quartz, zircon, columbite, massive green apatite, purple heterosite (secondary after triphylite), and uraninite. The uraninite analyzed by Hillebrand¹ in 1889 was from this quarry. It will be noted that the quarry is within the limits of the town of Portland, not in Glastonbury as stated in most references. A single blast about the year 1884 yielded 100 kilograms or more of columbite, the largest single yield from one pocket known in this vicinity. The entire mass was without crystalline planes.

     Of the quarries active at the present time, the Strickland quarry at Collins Hill, Portland (Locality 3), is the most productive, and the best known.² Mr. F. E. Strickland, the owner, is an expert on the minerals of his quarry, and saves carefully any unusual crystals. The quarry was opened as early as 1840. There is a pitcher, bearing in gilt the name of Strickland, now preserved in Wesleyan Museum, which was made from feldspar taken from the quarry at that early date. For many years the quarry was inactive, but recently it has produced the best grade of feldspar known in the region. It is the only quarry in this part of Connecticut which has yielded asbestiform tourmaline, purple apatite, lithiophilite, and nailhead calcite. The greater part of the uraninite from Portland has come from a small area near the hanging wall of the quarry. Other minerals reported are sphalerite, pyrite, smoky, rose, and citrine quartz, pink (caesium) and aquamarine beryl; garnet, microcline, cleavelandite, spodumene, pink and green tourmaline, muscovite, biotite, lepidolite, cookeite, pinite, kaolinite, columbite, purple, and massive green apatite, and autunite. While not strictly a pegmatite mineral, iolite has been found within the Bolton schist a few centimeters from its contact with the pegmatite.

     The Pelton quarry (Locality 4) has long been inactive. It probably produced a number of rare minerals in its day, but it is now known as the source of two minerals, unique for the region, bismutite and samarskite. Beryl and crystals of muscovite from the locality may be found in the Wesleyan museum. Another quarry long inactive is the Nathan Hall quarry (Locality 5). It is still noted for the abundance of the rose quartz to be obtained from its dumps. No other quarry compares with it in its yield of this mineral.

     The Swanson quarry (Locality 7) lies far back from the road, along a cart-path leading east from the main road past the relatively new Swanson homestead. It is a road (not shown on the map) which follows the township line. Although the opening is not worked now, there is a great deal of lepidolite to be found, and some triplite. Within the district triplite has been found only at this quarry. The mineral is intimately intergrown with a dark blue, massive tourmaline. It was with the expectation that the lepidolite might be shipped to Germany as a source of lithium that the quarry was opened, just before the war. It is reported that shipments got no farther than the dock.³

     On the west side of the river in the vicinity of the village of Haddam, there are a number of old mineral localities. Mr. E. W. Hazen of Haddam kindly conducted Professor W. N. Rice and the writer to several of the openings last summer. One of the chance finds of the region was made in a roadside quarry, later used as a cellar (Locality 10). A number of chrysoberyls and garnets were unearthed, but there is no record that other minerals were found. The house built over the site was later removed. No further attempts were made to obtain more minerals.

     On the hill across the road from this locality there is an abandoned quarry on land owned by Mr. Hazen (Locality 11) from which small plates of autunite may be obtained. Following the pegmatite ridge southward the Haddam epidote locality is reached. (Locality 12). A number of old collections have well crystallized specimens of clear epidote from this opening. There is a blast hole at the foot of a steep slope facing toward the east where the pegmatite dike dips beneath the meadow. With pick and shovel the moss and rubble were removed, and a limestone was disclosed in contact with the pegmatite. At the contact the limestone is transformed to epidote and garnet. Pockets of the more finely crystallized epidote are included in the more massive material. There have been no transparent crystals found at the locality for a number of years.

     The road which lies to the south of the epidote locality leads toward the west and crosses a small brook. A hundred meters or so beyond the brook one climbs to the crest of a pegmatite ridge. Going southward along the crest for two hundred meters, one comes to the Tims Hill Locality (Locality 13). Associated with the contact of the Haddam gneiss with the Middletown series there is a peculiar type of pegmatite consisting of oligoclase, biotite, short, doubly terminated black tourmalines (5 to 10 mm. in length), and crystallized iolite showing alteration to fahlunite. Gahnite and allanite are also reported from the locality. Professor Rice and the writer attempted to relocate the blast hole from which the iolite came, but without success. Professor Rice had visited the locality many years ago, and had detailed notes on its situation. It was very apparent that we were in the immediate vicinity, but no trace of the peculiar pegmatite could be obtained.

     There are a large number of quarry openings along the state highway between Middletown and Haddam. None of them, however, is known to have produced rare minerals, except the Toll Gate quarry (Locality 15). The opening has been long since abandoned, and is fast being overgrown. It is situated slightly north of the highway. The road cuts across the southern end of the dike in making an abrupt turn to the southeast. In addition to the usual tourmalines and beryls, the quarry is known for the large size of a number of columbite crystals which were taken from it many years ago.

     The ridge of pegmatite dikes through which the Connecticut river has cut in passing from the Newark sandstones to the crystalline rocks of the Eastern Highland is a prominent feature in the landscape as one looks eastward from Middletown. The ridge is known locally as White Rocks. Somewhat east of the ridge most conspicuous from Middletown, and south of the river, there is a feldspar quarry (Locality 16) which has been intermittently worked for a number of years. The locality is not especially rich in rare minerals, but occasionally odd varieties of the pegmatite types may be found. Opaque pink and green tourmalines may now be obtained. Lepidolite, uraninite, zircon, columbite, large, opaque beryls, microlite, and garnet are other minerals reported from the locality in the past.

CHARACTER OF THE PEGMATITIC INTRUSIONS

     It may not be out of place to make a brief statement concerning the method of intrusion of the pegmatite dikes into the Bolton schist. The exposures at the Strickland quarry are interesting in making clear the character of the intrusions. The bodies are not, usually, cross-cutting as would be inferred by the use of the term "dike." The magma, while still in a fluid or viscous condition, seems to have been folded into the pliant schist, as putty is folded into the rolls of the paper in which it is contained. Thus, while the magma was intruded during the Appalachian mountain building of New England, it crystallized after that event, and has not been rendered schistose by any subsequent movements. The shattering of the walls of some of the gem-pockets in the pegmatite tells of violent disturbances by earthquake movements, and the recementation of the fragments by pneumatolytic minerals, such as tourmaline and apatite, indicates that openings have allowed gases to escape from deep-seated sources. But there have been no crushing movements to metamorphose the pegmatites as a whole.

MINERAL LOCALITIES NOT PEGMATITIC IN ORIGIN

     There are two or three mineral localities in the vicinity of Middletown which are not associated with pegmatite dikes. The best known of these is the Old Silver Mine, situated approximately three kilometers east of the center of the city (Locality 17). During the Revolutionary War the mine was worked for lead, which was fashioned into bullets. Slash veins occur in the crush zone along the great fault between the Bolton schist and the Triassic conglomerates. The minerals found are galenite, sphalerite, pyrite, marcasite, chalcopyrite, quartz, calcite, and fluorite. The pyrite is frequently found in cubes, elongated parallel to one axis. Dana describes it as "capillary" pyrite, but the diameter of the rods is generally too large for such an appellation.

     South of Great Hill, north of Cobalt (Locality 6), at an elevation of approximately 450 feet, disseminated masses of chloanthite, and niccolite are found in the Bolton schist. Arsenopyrite and lollingite are found in quartz veins associated closely with the cobalt minerals: The locality has been worked over so frequently that there are few specimens to be obtained at present.⁴

     The following is a list of thirty-eight minerals which have been reported from the pegmatite dikes in the vicinity of Middletown, Connecticut.

Molybdenite, Microcline, Tourmaline, Monazite, Sphalerite, Albite, Muscovite, Apatite, Pyrite, Oligoclase, Biotite, Triplite, Fluorite, Spodumene, Pinite, Lithiophilite, Quartz, Beryl, Lepidolite, Triphylite, Magnetite, Iolite, Cookeite, Torbernite, Gahnite, Garnet, Kaolinite, Autunite, Chrysoberyl, Zircon, Microlite, Uraninite, Calcite, Epidote, Columbite, Bismutite, Allanite, Samarskite.

     Seven other minerals are found, either at the Great Hill locality, Cobalt, or at the Old Silver Mine. The list includes the following minerals, making a total of forty-five more or less rare minerals from the region, of which twenty-two have been found at the Strickland quarry.

Chloanthite, Galenite, Arsenopyrite, Chalcopyrite, Niccolite, Marcasite, Lollingite.