MSA MEETING PROGRAM & PLACE
Franciscan Renewal Center, (Piper Hall),
October 17, 2024 @ 7.30 pm Arizona time
"Sphalerite - Not Just a Black Mineral”
Presented by Les Presmyk
Sphalerite with Calcite
11.2cm, Stari Trg mine, Trepca, Kosovo.
Les & Paula Presmyk Collection. Jeff Scovil Photo.
Sphalerite with Fluorite on Dolomite
14.5cm, Elmwood mine, Carthage, Tennessee.
Les & Paula Presmyk Collection. Jeff Scovil Photo.
Sphalerite with Quartz and Galena
14.1cm, Rucheng mine, Hunan, China.
Les & Paula Presmyk Collection. Jeff Scovil Photo.
* If you are receiving this as a REMINDER email and attending via Zoom, please scroll to bottom for Zoom Link.
* Meeting is on 3rd Thursday.
* Okay to bring refreshments.
* MEETING will be (In-Person and Zoom).
* Mineral of the Month: SPHALERITE
Okay to bring 1-2 examples of Mineral of the Month.
Our October 17, 2024 program will be presented by MSA's own Mr. Les Presmyk on "Sphalerite - Not Just a Black Mineral.”
Save the date on your calendars for debut of this very special program for Mineralogical Society of Arizona!
Sphalerite is the primary ore for zinc, a metal which was first identified and refined in India. Smithsonite, willemite and hemimorphite have also been mined for their zinc content. It is combined with copper to form brass and is an integral component in coating steel and iron to prevent oxidation (rusting). Zinc is a fairly reactive element, readily combining with other elements to form a myriad of colorful minerals like smithsonite, willemite, rosasite, legrandite and adamite, to name just a few. There is only one place where zinc occurs in its elemental form, at a locality in Australia where native zinc is found in basalt vesicles.
Zinc's primary ore mineral, sphalerite, occurs on most continents, although it is uncommon in Africa and Australia, and in fine specimens from all of these continents. It is commonly associated with galena, calcite, fluorite and quartz, along with pyrite, chalcopyrite and other sulfides. Iron is the most common allied element, accounting for why most sphalerite is black and can even be included in the chemical formula. Pure sphalerite is almost colorless and is simply zinc sulfide. Most of the sphalerite we see is actually zinc iron sulfide, which is sometimes referred to as marmatite. Transparent yellow to green crystals are called cleiophane.
In the United States, the most historically important sphalerite localities center on the Tri-State District, where the states of Kansas, Oklahoma and Missouri come together. Underneath this area is a series of huge lead-zinc deposits exploited for almost 150 years by hundreds of mines. The most notable sphalerite specimens from here include combinations of sphalerite and galena on dolomite, chalcopyrite crystals arranged epitaxially on sphalerite crystals and the beautiful red crystals known as "ruby jack". Other notable U.S. localities include a number of mines in Colorado, quarries in the Midwest, the Illinois-Kentucky fluorspar district, the Walworth and Penfield quarries in New York and the prolific mines near Carthage, Tennessee.
Canada has relatively few zinc deposits but the mine on Baffin Island has produced fine sphalerite specimens. There are quarries across the river from Penfield and Walworth that produce very distinctive orange sphalerite crystals. Mexico has a number of mines producing fine sphalerite specimens including Santa Eulalia, Naica, and Concepcion del Oro. Peru is probably South America's most prolific producer of well crystallized sphalerite.
Sphalerite localities in the United Kingdom and Europe are too numerous to cover in just a short time. England, the Isle of Man, and Ireland have all produced fine specimens over the past 200 years. Moving onto the mainland, zinc mines from Germany and Poland to Spain, Portugal, Bulgaria, Kosovo and Romania all have produced and continue to produce significant quantities of fine sphalerites, the best of which are associated with calcite, barite, apatite and even rhodochrosite.
Finally, the localities of Russia, Japan and China are significant as well. The mines at Dal'negorsk have been producing fine specimens for over 30 years and this continues to today. The sphalerite specimens from Japan on the market today were collected at least 70 years ago and more likely over 100 years ago. Red crystals of any size are almost non-existent in specimens because the Japanese faceted these crystals. The mines of China continue to produce fine sphalerite specimens, although with less frequency now than say, ten years ago.
Sphalerite is a mineral that occurs in large crystals and attractive associations. Compared to many other minerals, fine sphalerite specimens are still relatively reasonable. Fine specimens from Tennessee, Kosovo, China and Bulgaria can still be purchased for a few hundred dollars. So, when fellow collectors ask why I started collecting sphalerite, in addition to my main focus of Arizona minerals, I ask, why not?
Les Presmyk grew up in our club and sharpened his collecting & competitive edge at Mineralogical Society of Arizona (MSA) as a junior member before advancing to regional and national platform to compete and win at several major gem & mineral shows across the United States. He is currently an MSA Show Co-Chair and Exhibits Chairman of MSA's Phoenix Heritage Mineral Show.
Les retired seven years ago as the Principal Mining Engineer for Salt River Project, Arizona’s second largest electric utility. He and his wife of 47 years, Paula, are Arizona natives and are both graduates of the University of Arizona. Les has been actively involved in his community of Gilbert, Arizona for over 27 years, serving as the Islands H.O.A. president, Planning Commissioner, and Town Council Member for 12 years and additional roles since 2011. Most recently he founded the Veterans Advisory Board and is the current chairperson.
Les started collecting at the age of 10 and just attended his 61st straight Tucson Show. Their displays have received AFMS Regional and National Trophies, along with the Prospectors and Pearl Trophies in Denver, the Desautels, Lidstrom and Bideaux Trophies at the Tucson Gem & Mineral Show and the Bob Jones and David Shannon Trophies at MSA's Phoenix Heritage Mineral Show. They have been the featured exhibitors at the East Coast Gem & Mineral Show in Springfield, Massachusetts twice.
He is a past president of Mineralogical Society of Arizona (1989-1990), a past president of Tucson Gem & Mineral Society, current Chairman of the Flagg Mineral Foundation, a founding member of the University of Arizona Mineral Museum Advisory Board and appointed by Governor Ducey to the UArizona Mining, Mineral and Natural Resource Education Museum advisory board. He has served on the Tucson Gem & Mineral Show Committee for 38 years, including competitive exhibits and judging chairman for this entire period.
Les received the 2002 A. L. Flagg Distinguished Service Award, Is a charter member of the 2014 Mineralogical Society of Arizona Hall of Fame, and the recipient of the 2017 Carnegie Mineralogical Award.
He has explored and collected in a number of localities in Arizona, Missouri and Mexico and provided engineering expertise at the San Francisco mine in Sonora, Mexico, the Brushy Creek mine in Missouri and the Red Cloud mine in Arizona. Les has written numerous articles and co-authored “Collecting Arizona”. He has spoken at the Dallas Symposium, the Yale Symposium, and the Northwest Friends of Mineralogy Symposium, along with numerous Arizona and New Mexico Symposiums, the Tucson, Springfield, and Denver Shows, and clubs throughout the United States.
Thank you, Les, for your many contributions to our hobby and support of Mineralogical Society of Arizona!
Meeting starts at 7.30PM Arizona time.