The many colors and hues are tremendous!
Above is a light purple cube on top of a plate of sphalerite.
This piece of green fluorite is actually from Mexico, but occasionally, specimens of green were found in Illinois and Kentucky. A small region in extreme southeastern Illinois and extreme southwestern Kentucky, known as the Illinois/Kentucky fluorspar district, once supplied the nation with 90% of its need for this strategic mineral. After WWII, the supply chain changed dramatically, as will be discussed below.
This dark brown is actually from a thin coating of petroleum. Maybe one day a big oil discovery will be made in that area of the Midwest.
This specimen of amber-colored fluorite shows different stages of crystal growth. Cubes growing inside cubes are commonly called phantom crystals.
This being my second guest posting, a little background information may be appropriate. Do you wonder why my “handle” is Secret Aging Man? My wife, W2W, gave me this nickname for the blogosphere because of two watershed events -- a short essay I wrote in the fifth grade and a job search I did a couple of months ago. My essay, entitled "What Will I Be?," describes my future occupational aspiration, at the ripe age of 10 years. I ended it by prophetically stating… “I will either be a secret agent man or a geologist, but I think I will probably be a geologist.” Fast-forward 41 years later and I am in the middle of a new employment search. After four months on the hunt, an article on Yahoo! catches my eye. “The CIA and FBI are now hiring all positions! Start your new career, today!” After a few minutes of surfing their respective web-sites, the answer echoed loudly in my head - Dude, you are too old, way too old to even apply. I thought out loud “Hey! What about Sean Connery? If he can shave the world, sho can I!” After this little episode, my wife of great wit proclaimed me the Secret Aging Man.
I can’t talk about fluorspar without mentioning my parents, especially my father. My parents initially visited the Southern Illinois Earth Science Club to appease my curiosity about rocks, but soon their interest and passion for the hobby were just as high, if not more intense than my own. About the same time, my father started having heart problems and had to retire from his profession as a carpenter at SIU. He had lots of time on his hands and devoted most of it to his hobby and his club, serving as President, on more than one occasion. After his death in 1974 due to heart surgery complications, my mother, who had previously served as Secretary/Treasurer, took up the torch and served one term as President. The reason I mention all this is because my father was President of the club when legislation was enacted declaring fluorite as the Illinois State Mineral. This event would not have happened if not for the efforts of my dad and other members of the Southern Illinois Earth Science Club.
This large specimen of purple fluorite and white dogtooth calcite came into our collection in an interesting way.
My father and I were somehow introduced to an Ozark-Mahoning company geologist. Accumulated in his front yard were several large and attractive specimens from the fluorite mines, gifts from various miners trying to make a good impression and perhaps hoping for a little job security. My dad proposed a trade for the piece pictured above and presented several fine, hand-made pieces of jewelry, brought along just for the purpose of barter. The guy picked the tie-tac, and even though we insisted he take more jewelry in trade, he refused. We probably had $5 in that tie-tac. My ultra-antique road show appraisal of the piece pictured above is now $3500.
Monthly trips to visit our primary supplier, a preacher/miner friend in the back country of the Shawnee National Forest, were needed to feed our addiction. I haven’t a clue how to find his place now. I remember traveling for what seemed forever up and down hilly gravel roads, with clouds of dust following and sometimes overtaking our vehicle. We were always graciously welcomed and personally escorted to ‘round back of the old shed, where sheets of tin roofing graced the tops of concrete blocks, creating the entrepreneur’s store shelving. Upon the shelves, a virtual jewelry store of minerals sparkled like candy in the eyes of this young pebble pup. We never asked, but, according to common knowledge, the minerals were daily hoisted up from the mines in the miners’ lunch boxes. The mining company reluctantly went along with this practice until some overzealous miner broke an elevator, attempting to hoist a specimen of several hundred pounds. After that incident, the flow of new mineral specimens came to an abrupt halt. Anyway, we bought all we could afford for 25 cents per pound. W2W did a post a while back about a walk-about we did in the Shawnee Forest. We stopped by the American Fluorite Museum, in Rosiclare, and took a few pictures you may want to check out in her post.
So, is there any value to fluorite, other than as a nice collectible for the mineral enthusiast? Fluorite is comprised of Calcium and Fluoride (CaF2) and the 97%+ pure CaF2 mineral is used in the production of hydrofluoric acid. Ceramic-grade fluorite, containing 85%-95% CaF2, is primarily used for the production of glass and enamel, to make welding rod coatings, and as a flux in the steel industry. Less pure grades of fluorite are also used by the steel industry. And of course, we have all heard of fluoride in our toothpaste and drinking water. For many years, the addition of fluoride to our municipal water supplies has been hailed as a benchmark by public health advocates, who claim that it has drastically reduced the number of cavities in the overall population. However, critics of this policy have emerged, citing potential serious health threats from long-term ingestion of fluoride. Personally, I’m just not sure which side is right or if both have merits, but think the issue should be discussed and appropriate health studies conducted. The Illinois/Kentucky district supplied about 80-90% of the nation’s needs until a slow death spiral of the industry began sometime around 1950. Foreign imports from China and India, priced below our own production costs, eventually wiped out the domestic fluorite industry. The last domestic fluorite mine, located in Southern Illinois, closed in 1995.