MA 220px-Map of USA MA

Rockhounding Massachusetts

Massachusetts is a good state for rockhounding.  There are dinosaur track sites in the Connecticut River Valley.



State Rocks, Gemstones, Minerals, Fossils, & Dinosaurs

Rockhounding Tip:  Knowing state rocks, gemstones, minerals, fossils, and dinosaurs often can be very useful information for rockhounders.  Ordinarily, states with significant mineral deposits, valuable gemstones, fossils, or unusual or significant rock occurrences will designate an official state mineral, rock/stone, gemstone, fossil, or dinosaur to promote interest in the state’s natural resources, history, tourism, etc.  Accordingly, such state symbols often are a valuable clue as to potential worthwhile rockhounding opportunities.


Massachusetts - Rock - roxbury conglomerate

Roxbury Puddingstone

State Rock:  Roxbury Puddingstone (Roxbury Conglomerate) (1983)
Massachusetts designated the Roxbury Puddingstone (Roxbury Conglomerate) as its official state rock in 1983.  Roxbury Puddingstone is a puddingstone or conglomerate stone that forms the bedrock underlying most of Roxbury, Massachusetts, and now part of the City of Boston.  Puddingstone (aka pudding stone, plum pudding stone) is a common name used mainly in England for a conglomerate consisting of well-rounded clasts whose colors are in such marked contrast with the abundant fine-grained matrix or cement that the rock suggests an old fashioned plum pudding.  A prime example is the lower Eocene Hertfordshire Puddingstone in England, composed of black or brown flint pebbles cemented by white silica with or without brown iron hydroxide.  Roxbury puddingstone did not originate in the Boston area.  No one knows for sure where this rock formed; it has some affinities with rocks found in West Africa, and also shares traits with some South American rocks.  Geologists do agree that the Roxbury Conglomerate was deposited between 600 million and 570 million years ago somewhere in the Southern Hemisphere.  Plate tectonics carried it into North America about 200 million years later.


Massachusetts - gem - rhodonite


State Gemstone:  Rhodonite (1979)
Massachusetts designated rhodonite as its official state gemstone in 1979.  Rhodonite forms as hydrothermal deposits and in metamorphic rocks and is often found associated with black manganese minerals.  It varies in hue from a light pink to a deep rose or reddish pink.  It is named after the Greek word for rose, rhodon.  Its rose-pink color is distinctive.  On occasion, it is confused with Rhodochrosite that also is pink to red in color, but streaked with white minerals such as calcite and is reactive to acids.  Rhodonite does not react when tested with acids and usually is associated with black manganese and pyrite.


Massachusetts - Mineral - Babingtonite


State Mineral:  Babingtonite (1971)

Massachusetts designated Babingtonite as its official state mineral in 1971.  It is a black to dark green mineral.  Babingtonite is rather uncommon, and, outside of Massachusetts is found in Poona, India; Devon, England; and Baveno, Italy.


Massachusetts - fossil - dinosaur track

Dinosaur Tracks

State Fossil:  Dinosaur Track (1980)
Massachusetts designated the dinosaur track as its official state fossil in 1980.  Although dinosaur bones are lacking in the state of Massachusetts, tracks are common.  Several types of dinosaur prints are known from the state, including Eubrontes, Grallator, Anchisauripus, and Otozoum.  Rather than pick a single one of these, the legislature designated the generic "dinosaur track" to cover them all. 
 These tracks are found in Jurassic Period sediments from about 200 million years ago.  At that time, the supercontinent of Pangea was rifting apart and the Atlantic Ocean was beginning to form.  Mudflats along the western shore of this new seaway provided the perfect environment for the preservation of the footprints of dinosaurs that passed along the beaches. 
 The first dinosaur tracks in Massachusetts were discovered in 1802, and more have been discovered during the subsequent two centuries.  The Dinosaur Footprint Reservation at Mt. Tom near Holyoke preserves a particularly good trackway record. 
In Granby, the prints of a theropod dinosaur fifty feet in length from head to tail (the first record of a theropod of such magnitude), was found.


Site - Dighton Rock

State Explorer Rock:  Dighton Rock (1983)
Massachusetts designated Dighton Rock as its official explorer rock in 1983.


Plymouth Rock

State Historical Rock:  Plymouth Rock (1983)
Massachusetts designated Plymouth Rock as its official State Historical Rock in 1983.  The Pilgrims, of course, did not actually land on Plymouth Rock.


Specimen - Granite (Fletcher Granite Quarry - North Chemsford, MA)

Fletcher Granite Quarry - North Chemsford, Massachusetts

State Building & Monument Stone:  Granite (1983)
Massachusetts designated Granite as its official building and monument stone in 1983.  The last Ice Age did leave Massachusetts with exceptionally fine samples of this rock; granite from Quincy was used to build the Washington Monument.

Rockhounding Resources

State-specific rockhounding books (including the books listed here as well as other books), regional rockhounding site guides, and other helpful rockhounding resources are identified - by category - in the Books & Gear section of Gator Girl Rocks with a link to the Gator Girl Rocks Amazon Store where you may easily browse selected resources and securely place an order.  Your order will benefit Charity Rocks!

Massachusetts State Geoloist logo - MA

Office of the Massachusetts State Geologist
Website includes useful information.


Conn Valley Mineral Club Logo

Connecticut Valley Mineral Club
A useful resource that includes Massachusetts’s rockhounding information.


  • James W. Skehan, Roadside Geology of Massachusetts (2001).
  • Peter Gleba, Massachusetts Mineral & Fossil Localities (1978).
  • Allan W. Eckert, Earth Treasures Vol. 1 - Northeastern Quadrant (1985; reprint in 2000).
  • James Martin Monaco & Jeannette Hathway Monaco, Fee Mining & Mineral Adventures in the Eastern U.S. (2d ed. 2010).
  • Kathy J. Rygle & Stephen F. Pedersen, Northeast Treasure Hunter's Gem & Mineral Guide (4th ed. 2008).


Museums of Interest to Rockhounders

Museum - Harvard Museum For Natural Science

Mineralogical Museum at Harvard University
Harvard Museum of Natural History, Harvard University – Cambridge, Massachusetts
The Harvard mineral collection ranks among the world's finest due to its very broad representation, wealth of rare species, and large number of specimens described in the scientific literature, and the quality of its display specimens.  The Mineralogical Museum was first built in 1891.  Today, a rich systematic mineral collection and displays of gemstones are the principal exhibits in the mineral gallery.  More than 5,000 exceptional mineral specimens representing 1,500 mineral species are displayed.  Many of the approximately 2,000 gemstones in the collection are on display.


Museum - Beneski Logo

Beneski Museum of Natural History
Amherst College - Amherst, Massachusetts
The museum has outstanding collections and its exhibits include vertebrate and invertebrate paleontology, minerals, and other geologic specimens.  The museum’s collection also includes the world-famous "Noah's Raven," tracks discovered in 1802 in South Hadley, Massachusetts.  This specimen constitutes the first dinosaur fossil to be collected in North America – 40 years before dinosaurs were even recognized as a distinct fossil group.


Museum - Springfield Museum logo

Springfield Science Museum
Springfield, Massachusetts
The museum’s ‘Dinosaur Hall’ includes replicas as well as some dinosaur fossils.  The museum exhibits rocks, minerals, and fossils.



Places to Visit - Interesting Sites To See

Site - Plymouth Rock Monument

Plymouth Rock
Pilgrim Memorial State Park - Plymouth Massachusetts
The granite rock, upon which the sea-wearied Pilgrims from the Mayflower first impressed their footsteps.  The top (visible) 1/3 of Plymouth Rock weighs approximately 4 tons.  The bottom portion (under the sand) weighs approximately 6 tons.  The Rock as it exists today is estimated to be only about 1/3 to 1/2 of its original size - the top half has been dragged around town, broken, and chipped away at by 18th and 19th century souvenir hunters.


Museum - Dighton Rock

Dighton Rock
Dighton Rock State Park - Berkley, Massachusetts
Dighton Rock is a 40-ton boulder originally located in the riverbed of the Taunton River at Berkley, Massachusetts (formerly part of the town of Dighton).  Dighton Rock is noted for its petroglyphs - carved designs - of ancient and uncertain origin, and the controversy about their creators.  In 1963, during construction of a cofferdam, state officials removed the rock from the river for preservation.  It was installed in a museum in a nearby park (Dighton Rock State Park).


Dinosaur Footprints - Holyoke

Dinosaur Footprints
Mt. Tom near Holyoke
This site includes more than 130 tracks revealed in slabs of sandstone. Researchers believe these prints were left by small groups of two-legged, carnivorous dinosaurs, up to 15’ tall.  The entire Connecticut River Valley – which scientists believe was a sub-tropical swamp a “mere” 190 million years ago – has long been recognized for its wealth of prehistoric footprints.


Site - Nash Dino Track Site

Nash Dinosaur Track Site & Rock Shop
South Hadley, Massachusetts
The Nash Dinosaur Track Site and Rock Shop is located about one mile from where the first dinosaur tracks in the Connecticut River Valley were found in 1802 by a farmer named Pliny Moody.  Visitors can see dinosaur tracks.  The site also includes a commercial rock and fossil shop.

Rockhounding Sites for Children & Families

Betts Manganese Mine – Plainfield, Massachusetts
Commercial (fee access) business. 


Historic Lead Mines near Loudville, Hampshire County, Massachusetts
The dumps at the historic lead mines are collected for mineral specimens.


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