Previous Meetings

May 2008

BMC Meeting – Tuesday, May 6, 2008 -- 7:30PM

The Estes Quarry, W. Baldwin, Maine: A New Pegmatite Mineral Locality -- Presented by Gene Bearss
At our May meeting, the BMC welcomes Gene Bearss, of Sanford, Maine, a well-known field collector and micromounter, who will speak to us about the minerals of the Estes Quarry in W. Baldwin, Cumberland County, Maine. Gene co-authored an article describing this fascinating new locality in the November 2000 issue of Rocks & Minerals. According to the article, the granite pegmatite at the quarry is highly unusual for New England, exhibiting pervasive layering like that at the Brown Derby pegmatite in Gunnison County, Colorado. Structural similarities with the famous pegmatites of the Pala district in southern California suggest a similar origin. The Estes pegmatite is classified as a beryl-columbite-phosphate subtype of the beryl-type pegmatites belonging to the rare element class. All of this makes for some very interesting minerals, over 40 of which have been found at Estes, including fine examples of fairfieldite, eosphorite, montebrasite, and vivianite. Gene has beautiful photographs of all the rare minerals at Estes and he will be sharing these with us.

To complement the presentation, club members are encouraged to bring in phosphate mineral specimens from their collections, particularly those from New England.
The Harvard Mineral Museum should be open starting at 7:00 PM. Please note: Because our guest speaker has a very long drive to and from the meeting, we will start the presentation by 7:30 PM, earlier than usual. We will hold a brief business meeting and field trip report after the presentation. As usual there will be refreshments and a mineral raffle. Please bring in any specimens you’d like to show us from recent BMC field trips. Also, invite a friend if you’d like -- guests are always welcome to attend our meetings.

April 2008

Rare-Earth Minerals - Dr Anthony Mariano

At our April Meeting the Boston Mineral Club welcomes back Dr. Anthony Mariano. Tony has considerable experience as a mineral exploration geologist, and has worked throughout the world with ore and gem deposits, and with rare-earth element (REE) mineral deposits, the topic of this evening’s presentation.

Tony writes: “The current demand for rare-earth elements has fueled a strong response on exploration for REE-bearing minerals on a world level. This talk will focus on minerals and geologic environments that comprise the major source of REE and yttrium. Examples will also be shown of some of the less common REE and yttrium minerals.”

A rare-earth mineral is one which contains one or more of the 15 rare-earth elements (the lanthanides of the periodic table) and/or yttrium. All rare-earth mineral species have a name with a chemical-symbol suffix, called a Levinson suffix, which indicates the predominant rare-earth element present. For example, monazite-(Ce) is a mineral with cerium as the predominant -- but not necessarily the only -- rare-earth element present.

There are hundreds of important high-tech and environmental applications for the rare-earth elements, making REE minerals economically quite valuable. These minerals can also be fascinating to collect. Though many are inconspicuous or unattractive, some are actually quite beautiful and even gemmy - like the color-change bastnäsite crystals coming out of Pakistan in recent years.

The following rare earth and yttrium minerals have been reported from New England:

Carbonates: ancylite-(Ce); bastnäsite-(Ce); kamphaugite-(Y); kainosite-(Y); lanthanite-(Ce); parisite-(Ce); synchysite-(Ce), synchysite-(Y)

Phosphates: florencite-(Ce); monazite-(Ce); rhabdophane-(La), rhabdophane-(Nd); xenotime-(Y)

Oxides: cerianite-(Ce); davidite-(La); euxenite-(Y); fergusonite-(Y); polycrase-(Y);
samarskite-(Y); yttrocolumbite-(Y);

Halides: fluocerite-(Ce)

Silicates: allanite-(Ce); britholite-(Ce); cerite-(Ce); chevkinite-(Ce); gadolinite-(Ce), gadolinite-(Y);
hingganite-(Y)

To complement the presentation, club members are encouraged to bring in rare-earth mineral specimens from their collections.

March 2008 Meeting

Tuesday March 4, 2008
Topic: New Hampshire Mineral Species Collecting - Tom Mortimer

Our March speaker, Tom Mortimer, is a longtime collector of New Hampshire minerals and is a
past president of both the Nashua Mineral Society and Micromounters of New England. Tom's
presentation will feature a slideshow of specimens from his extensive collection of New Hampshire
species. He has been an avid field collector for many years and has collected at both well known
and obscure localities throughout the state. A major focus of his ongoing collecting efforts is to
collect as many different mineral species as possible from within the boundaries of the state.

To complement the presentation, club members are encouraged to bring in some of their New
Hampshire specimens, especially those of rare or unusual minerals. This promises to be an
enjoyable and informative evening, one that should definitely spark our enthusiasm for the
upcoming field collecting season.

February 2008

BMC Meeting: Tuesday, February 5, 7:30 PM
" Collisions big and small: An Imperfect History of the Solar System "
Professor Sarah Stewart
Harvard Department of Earth and Planetary Science

At the February meeting of the Boston Mineral Club we welcome back Professor Sarah Stewart of Harvard’s Department of Earth and Planetary Science. Dr. Stewart last visited the BMC four years ago. She discussed Martian Geology, craters, water on Mars, and showed us her new lab.

Professor Stewart’s field of study includes the composition and evolution of planets and small bodies such as asteroids and comets. In her Shock Compression Laboratory, her research group conducts experiments on the dynamic response of rocks and minerals to measure fundamental material properties. She has a cannon in her lab.

She will talk about collisions and the formation of the solar system:

Impact events have shaped our solar system. Early in the solar system, slowly colliding planetesimals merged to grow into planets. At later times, fast collisions led to mutual destruction of minor planets and the formation of debris fields like the asteroid and Kuiper belts. The history of collisions in the solar system is recorded on planetary surfaces and by the debris fields.

I will present new results on the fragmentation of bodies, from cm-size to planets, and the implications for the evolution of the whole solar system. Then, I will focus on the way that collisions have affected the ancient material in the Kuiper belt, which will be visited by spacecraft in 2015.

She adds that “the talk topic is not terribly mineralogical, but you will see that composition matters a lot. I'm happy to give a short lab tour after the talk.”

Professor Stewart received her Ph.D. at Cal-Tech in 2002 in the field of Planetary Sciences, with a minor in Astrophysics. She returned to Harvard in 2003, having earned her B.A. in Astronomy & Astrophysics and Physics here in 1995.

Check out Dr. Stewart’s web site at http://www.fas.harvard.edu/%7eplanets/sstewart/, particularly the laboratory and research areas.

In lieu of our usual honorarium, Dr. Stewart expressed interest in adding to her (new?) mineral collection. Perhaps a few of us could bring in a good New England specimen for her.

The Harvard Mineral Museum should be open starting at 7:00 PM. At 8:00 we will hold a brief business meeting and will try to start the presentation by 8:15. Short lab tour following the talk.