Friday, October 29, 2010

Maryland's Embarrassing State Gemstone

Six years have passed since then Governor Erlich signed legislation naming "Patuxent River Stone" as Maryland's State Gem. Meanwhile, many who are prominent in state gemological, geological, paleontological and mineralogical circles continue to express outrage. While the stone itself has merits, the grievances focus on a misleading official description of Patuxent River Stone as both agate and dinosaur bone. "An embarrassment to the State of Maryland" is the kindest language I've heard regarding the misrepresentation of a material that is in truth quartzite. Even the Maryland State Archives erroneously describe Patuxent River Stone as "agate, a cryptocrystalline form of quartz."

A look through the microscope at the slab of Patuxent River Stone featured in our title picture makes clear that despite appearances, it is neither agate nor fossilized dinosaur bone. Immediately apparent is an obviously textural rather than cryptocrystalline structure of sandstone metamorphosed into quartzite through tectonic compression.

The official web site (link provided in first paragraph) for this material, which labels it as Patuxent River AGATE, proclaims that a state gemstone should be beautiful, colourful, take a fine polish, be able to be fashioned into jewelry, and very notably be "rare but findable, existing in sufficient quantity to allow for a reasonable source of supply for local artisans." Agatized dinosaur bone is nowhere near that abundant in Maryland if it exists at all. For that matter, as the person responsible for the Maryland Minerals web site, I've never seen any kind of agate that was collected in Maryland and am unaware of any literature regarding its occurrence in the state, except in conjunction with "Patuxent River Stone."

To help me research this post, a prominent local gem cutter drove me to a pebbly stream not far from I-95 in White Marsh. Twenty years ago, most of this area consisted of sand pits where quartzite pebbles were extensively quarried for construction material. White Marsh lies on the Arundel formation, which runs diagonally through the center of Maryland extending even to the Eastern Shore. Dinosaur fossils have been reported in Arundel Formation deposits, but they consist of neither agate nor quartzite.

We crawled about the stream bed on hands and knees looking for
colourful quartzite pebbles. They were scarce enough that searching for them proved an enjoyable but very easy challenge. Pictured at right are a few that we picked up. A presence of iron speaks for their colour, and no doubt they would polish beautifully.

Meanwhile, Maryland, unlike numerous other states, does not have a State Mineral or a State Rock. Since Maryland was once the world's second leading producer of chromium, a good choice for State Mineral could be chromite. Yet, what better choice for a Maryland State Rock than quartzite? And who is to say that quartzite should not qualify as the State gem if sufficiently graded for colour?

So why does our State Gem continue to be incorrectly touted as agatized dinosaur bone? " Those not into the hobbies could care less," my gem cutter friend replied." Then, requesting for political reasons that I not use his name, he added: "To guys like you and me it's an embarrassment, and even worse, you've got all this false information being passed on to school kids."

Monday, October 18, 2010

Southwestern Maine Gem and Mineral Localities

Two days of a recent New England vacation largely devoted to food, foliage, and hiking, were booked to collect minerals in Maine. On the first of those days, rain fell in torrents that made seeing for more than a few yards while driving a challenge. Needless to say, it deterred me from collecting, but not from six hours of driving through the southwestern part of the state to plan an itinerary for once the weather cleared. This driving ultimately spared me from time-consuming wrong turns the next day, when conditions had become conducive to collecting. They were so bad that first day that I even managed to drive by, look for, and not even see the little sign along Route 26 near the high school heralding the Poland Mining Camps.

Founded by the late Irving "Dudy" Groves (1919-2005) and taken over by his widow, the engaging and hospitable Mary Groves (left), it is the ultimate destination for anyone serious about collecting the gem and mineral bounty for which Oxford and Adroscoggin Counties are renowned. Though tourmaline is king, a myriad mines, prospects and quarries in this part of Maine offer up a vast variety of minerals desirable for just about any collecting niche. My friends Robert and Stephanie from the Baltimore Mineral society spent a week at Poland Mining Camps during the summer of 2009. They were kind enough not only to load me up not only with printed material about the local mineralogy, but also facilitate my visit to the camp and an opportunity to confer with Mary Groves.

My agenda was to visit the Tamminem and Harvard Mines mentioned in our Mineral Bliss post of August 15, 2009, which was based on a talk by Nancy Millard at the recent Atlantic Coast Gem and Mineral Show in West Springfield, Massachusetts. The two pegmatite localities are in walkable proximity to one another and among a minority of localities in this region that are open and accessible to the public. Even before I arrived at Poland Mining Camps, Mary had placed a call to assure that I would be welcome to collect.

While both The Tamminem and Harvard Mines are destinations for the Camp's field trips, they have been mined to a greater extent than other localities that Poland Mining Camp either owns (Mt. Apatite is one of them) or enjoys exclusive access. Information that also lists the minerals known to have been collected at each locality and even includes a map is available through a link on the the Poland Mining Camps' web site. A Collector's Guide to Maine Mineral Localities by W. B. Thompson, D.L. Joyner, R.G. Woodman, and V.T. King is also available on line, courtesy of the State of Maine. It offers additional information that includes specific instructions on how to reach many of the localities.

From the Poland Mining Camps, I found my way to the parking area for Tamminem and Harvard Mines on Richardson Hollow Road less than a mile from its intersection with Greenwood Road in Oxford County. The Tamminem Mine is but a short walk downhill from the parking area. It yielded me plenty of unremarkable schorl and some decent clevelandite. Because Mary had specifically instructed me to look for it, my most rewarding find was the micro blue apatite pictured at right. Knowledgeable collectors with properly trained eyes stand a chance of finding rare pollucite crystals here along seams in petalite, which though said to be common, can be difficult to visually differentiate from feldspar.

A visit to the Harvard Mine entails a hike of about a half mile up the side of a mountain on a blazed trail that sets out directly across across Richardson Hollow Road from the parking lot. Although known for having produced fine fluorapatite crystals as well as some lustrous cassiterite, I found not a trace of either. A magnificent view and abundant pickings of showier schorl than at the Tamminem along with plenty of reasonably attractive almandine crystals made collecting at the Harvard a lot more fun than the Tamminem.

My destination for the evening was North Conway, New Hampshire, to which I headed via a circuitous route that passed not far from the Lord Hill Mine near Stoneham in Oxford County. It is open to the public and is known for giant quartz crystals, large blue as well as colourless topaz crystals, and also many of the rare phosphate species for which the Palermo Mine in North Groton New Hampshire is famous. Getting to Lord Hill entails navigating a potentially confusing array of dirt roads and then hiking for a little more than a mile. I did not reach the vicinity of Stoneham until too late to get to the mine and back by dark.

Next summer, I hope to return to this part of Maine and if a long enough time frame proves feasible, look forward to the Poland Mining Camps being my base. Either way, a visit to Lord Hill will be on the agenda.