19 pound 11" Brassy GOLDEN PYRITE Pyritohedral Crystals -Peru

This year in Tucson the wholesale price for good Peruvian pyrite specimens was triple what it was two years ago in 2011. I asked several dealers about this, and was given several reasons:


Rock face showing embedded pyrite crystals

by David Rusterholz

David contacted me in the summer of 2015, to ask about going to Navajun to collect. He is an avid collector, Chemistry Professor Emeritus at the University of Wisconsin-River Falls, and President of the St. Croix Rockhounds of Stillwater, MN. David asked a bunch of questions about what it is like collecting at Navajun. Apparently I answered his questions satisfactorily because in late November he and his wife Becky Kleager made the pilgrimage to Navajun, Spain to do some pyrite collecting at Mina Ampliación a Victoria. Below is his report. -Eric

by Eric Greene

INTRODUCTION

Mina Ampliación a Victoria is a pyrite deposit about 4 kilometers north-northwest of the tiny village of Navajún, in the Cervera district in La Rioja province, Spain. The surrounding area forms the headwaters of the Barranco de la Nava in the Sierra de Alcarama foothills of the Iberian Range. The deposit was discovered in 1965, and, through the years, pyrite from Navajún has been appreciated by and highly sought after by mineral collectors for its unique, highly aesthetic, exquisitely sharp, brightly lustrous, near-perfect single cubic crystals, clusters of interpenetrating crystals, and crystals embedded in matrix. Arguably the finest cubic pyrite crystals in the world come from Navajún (not Logrono, as they are sometimes mislabeled). The degree of perfection of these crystals causes many neophytes to exclaim in amazement and ask if they are manmade. Because of its beauty and perfection, Navajún pyrite has become the icon of Spanish mineralogy since its discovery.

  • Created By : 20-Dec-2014
  • Write By: tmmadmin
  • Published In: Mineral Species
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7.5" pyrite group of 38 cubic crystals to 1.6" - Logrono, Spain

Pyrite, or iron pyrite - infamously known as "Fool's Gold" - is a shiny, brassy-gold mineral that is commonly mistaken for gold. It can have sparkling, mirror-bright luster, and forms in a vast variety of interesting crystal habits, which makes it extremely popular among mineral collectors. Pyrite is the most common of the sulfide minerals - a group which includes galena, sphalerite, chalcopyrite, and arsenopyrite. Ironically, despite its "fool's gold" nickname, pyrite and gold are often found together. Actually, it's easy to tell the two apart, as pyrite is much lighter in color, less dense, and harder (gold can be scratched with a knife or fingernail).


by Eric S. Greene

Having the chance to collect pyrite at Navajún, Spain has been #1 on my bucket list since I first saw specimens from Mina Ampliación a Victoria. Now, after a buying trip to Sainte-Marie-aux-Mines in France, my dream was about to come true. It was the 4th of July. My wife Jeanne and I were celebrating America's Independence Day by visiting the Guggenheim Museum in Bilbao, then heading south to Navajún to meet mine owner Pedro Ansorena Conde and dig for pyrite. The drive from Bilbao takes about 3½ hours on a superhighway that passes over and around rolling hills and mountains studded with state-of-the-art windmills and field after field of wine grapes, wheat and hops. The last 40 km of the trip takes over an hour because the road winds through small villages and up, down and around hairpin turns on the way to our destination.

  • Created By : 20-Apr-2017
  • Write By: tmmadmin
  • Published In: ROOT
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Chalcopyrite is a brassy yellow mineral with the chemical composition CuFeS2, or copper iron sulfide. It is found in most sulfide mineral deposits around the world. Chalcopyrite loses its surface metallic luster and brass-yellow color when it weathers, changing to a dull, gray-green color. When acids are present, the color can become brilliantly iridescent purple, violet, blue or green. Chalcopyrite is most easily recognized by its brassy yellow color, metallic luster, and high specific gravity, which give it an appearance similar to pyrite and gold. Unlike these minerals, chalcopyrite is brittle and has a unique greenish-gray streak, and unlike pyrite, is easily scratched with a nail.