• Created By : 13-Jan-2017
  • Write By: tmmadmin
  • Published In: Mineral Species
  • Hits: 54
  • Comment: 0


1.5" Fine Gemmy Green FLUORAPATITE Sharp Terminated Crystal Panasquiera

The name apatite comes from the Greek word apatein, meaning to deceive, because of its similarity to so many other minerals. Ironically, it is actually 3 different minerals, and the precise species of this phosphate mineral depends on which of 3 ions is predominant:

  • If fluorine is the primary ion, then it is fluorapatite - Ca5(PO4)3F
  • If chlorine is the main ion, then it is chlorapatite - Ca5(PO4)3Cl
  • If the hydroxyl group is dominant, then it is hydroxylapatite - Ca5(PO4)3OH

However, in the crystal lattice these ions can substitute freely, so all 3 are typically present in any one specimen, making it impossible to distinguish them without x-ray diffraction or other analytical methods. Most collector forms of apatite are fluorapatite.

Apatite is the most common phosphate mineral. It is the primary source for phosphorus, a fertilizer required for plant growth. Also, the teeth and bones of humans and most animals, are composed of hydroxylapatite.

  • Created By : 02-Dec-2016
  • Write By: tmmadmin
  • Published In: Your Collection
  • Hits: 135
  • Comment: 0

Some, but not many of us mineral collectors are blessed with unlimited space to display and store our mineral collections. Even in our 13-room house, we don't have space for everthing (and Jeanne has a rule: no mineral specimens in the part of the house we live in!). So, like other factors to consider in building a mineral collection (color, quality, species, locality, etc.), size does matter, and collectors must think about what size they want to collect. For example, consider this: you can display 1,000 thumbnail-sized specimens in the the space required to keep 50 hand-sized specimens. That certainly puts it in perspective!

Here are the names for the different sizes that I use as "standards".

CONTINUED FROM PART 1


4.1" Fat Hoppered SCEPTER QUARTZ Antique White on Smoky Stem

Tuesday, September 20, 2016

Today was a mineral shopping day in Araçuai. We visited 4 warehouses: Mineração Zé da Estrada (run by the owner of the hillside in Taquaral with all the mines that we visited yesterday), Tony Gemas Mineração, Marcos de Zé da Estrada, and Emerson Murta's Ie Pedras do Brazil. I got some fantastic cathedral quartz and cathedral citrine, half a dozen pieces of superb black kyanite (best I have ever seen), some nice rose quartz crystals, brazilianite, and several outstanding specimens of the rare phosphate mineral eosphorite. 

by Eric Greene

 

INTRODUCTION

In September of 2016 I embarked on a private 10-day guided tour of the mining towns of Minas Gerais, Brazil. Why Brazil? If you love crystals and minerals, Brazil is the dream destination, sure to top your bucket list of must-see places in the world. The mineral tour was organized and led by Pedro Paulo Pinto, an experienced English-speaking guide who owns a travel agency in the colonial mining town of Ouro Preto. I was the only person on the tour, which included stops in some of the best-known mining towns in Minas Gerais, trips to a number of underground and open-pit mines, and visits to the shops and warehouses of over two dozen mineral dealers. This is my journal from the 18 days I spent on this amazing trip-of-a-lifetime for this mineral collector.

MINAS GERAIS

Minas Gerais is in southeastern Brazil, and its capital, Belo Horizonte, is about 250 miles NNW of Rio de Janeiro. Minas Gerais (which translates as "General Mines") is the fourth largest state in Brazil, and it is the country's best-known mining province, famed for its fine gemstone specimens of tourmaline, topaz, various members of the beryl group (emerald, aquamarine, morganite and heliodor), in addition to abundant quartz, (found in various forms including smoky quartz, citrine and rose quartz). The region's abundant pegmatite mines also produce other less well known gem minerals such as kunzite, chrysoberyl, euclase, and brazilianite. In addition, the state has huge reserves of iron and sizeable reserves of gold and diamonds, and is a major producer of milk, coffee and other agricultural commodities. It is about 1,300 miles south of the equator, and has a humid subtropical climate.

Many new mineral finds make their premiere appearance at one of the many mineral shows in Tucson, Arizona, every year in February.  But at the 2014 East Coast Mineral Show, a significant and dramatic new find of highly aesthetic specimens showed up for the first time (Polityka 2014).  It consisted of almandine garnet crystals embedded in a shiny, dark silver graphite matrix; these were collected at the Red Embers mine in Erving, Franklin County, Massachusetts.  The graphite matrix had been selectively removed from both the front and back sides to expose the garnets, allowing light to shine through them, revealing the glowing, vivid burgundy-red color of the transparent gem almandine.  These specimens caused a minor uproar and were an immediate success, judging by the buzz of the crowds blocking the aisles around the booth set up by Jay Baskin of Jay's Minerals, located in New Jersey. Throughout the building people were raving about this new material, which has an extremely high “wow factor.”  The next year at the 2015 East Coast Show, Baskin returned with a new supply of this material that he had prepared over the previous year.  Buyers again lined up to purchase specimens of this extraordinary new material, including major players such as the American Museum of Natural History, the Harvard Mineralogical and Geological Museum, Yale University, the University of Arizona, and others (Polityka 2015).

Here is the latest word on the current situation at the Rogerley Mine in England, direct from Jesse Fisher.