Printer Friendly

Bilbao and Barcelona shows 1998.

The Spanish mineral specimen market was highlighted in 1998 by a world-class discovery of pyromorphite from the San Andres mine. Pyromorphite from this locality is well known, and fine specimens (in limited quantity) reached the mineral shows about 10-15 years ago. However, after the official closure of the mine in 1990, many areas of the mine caved, and no new specimens reached the market. In the fall of 1997, two Andalusian collectors worked a small tunnel in the collapsed area, using a telescoping tube made of sheet steel. After some months of work, they reached the mineralized area, and obtained more than a thousand fine pyromorphite specimens, from thumbnail to cabinet size.

Pyromorphite crystals to 1 cm fully cover matrix, or in small specimens form floater groups of crystals. The matrix is in most cases earthy limonite. The color of the pyromorphite from the San Andres mine is a spectacular bright apple-green, very attractive and lustrous. Only in a few specimens is barite or rarely cerrusite found in association.

Immediately after the discovery, the Spanish dealer Jordi Fabre secured the better specimens of the lot, mainly those obtained from a particular pocket (named "geoda La Victoria" by the finders) found around the last day of work. In this pocket, the pyromorphite crystals are associated with barite. The largest specimens from this pocket caused a great stir at the 1998 Tucson Show, and sold immediately. (See vol. 29, no. 3, p. 214-216.) At the Bilbao and Barcelona shows, Jordi Fabre, Luis Miguel Fernandez, from Zaragoza and Juan Pena, from Sevilla had more fine pyromorphite specimens from San Andres mine.

And a note about the locality. The nearest town to the mine is Villaviciosa de Cordoba, but the mine is actually in Espiel. The specimens may be precisely labeled as follows.

Mina San Andres Grupo minero Ciclope Cerro del Bufalo Espiel (Cordoba) Espana

San Andres mine Ciclope mining district Buffalo Hill Espiel, Cordova province, Spain

Another interesting find from Spain is the native silver from the Balcoll mine, Falset, Tarragona province. The mine is also a "classic" locality, like the San Andres mine, but much older, dating from the beginning of the century. The silver specimens were found by Joan Abella, while searching some calcite-dolomite blocks in the dumps of the mine. The blocks had been dumped there about 1905. Most specimens are composed by silver filaments, but some have oriented growths of very elongated skeletal crystals up to 7 mm, forming the typical "herringbone" habit. These are the finest silver specimens found in Spain in many years.

The silver was found inside masses of crystalline carbonates that were dissolved with acid. In some specimens silver is partially altered to acanthite. Other specimens include millimeter-size acanthite crystals, cubes with octahedral modifications, but not directly associated with the silver. Jordi Fabre had specimens at the Bilbao and Barcelona shows, and Joan Abella, the finder, also at the Barcelona show, in the booth of the Grup Mineralogic Catala.

Juan Pena also had other interesting Spanish minerals. Among them were colorful (but unfortunately unstable) iron sulfates such as voltaite, coquimbite, botryogen and others from the abandoned subterranean workings in the area of the Alfred pit, Riotinto mine, Riotinto, Huelva. From the same locality Juan Pena also had specimens of crude microcrystals of covellite covering the surface of massive pyrite.

Goethite is a very common mineral, but crystals are rare. At the Bilbao show Zona Minera, from Madrid had some small calcite geodes from Tordelrabano, Guadalajara province, with laminar goethite crystals up to 7 mm long. Small anatase crystals on quartz crystals are still appearing from a roadcut near the old tin mine in Penouta, Viana do Bollo, Orense province. There are also cassiterite specimens from the Penouta mine, found as relatively crude twinned crystals, up to 5 cm. The primary source of these specimens is Jose Fernandez, from Villamartin de Valdeorras, Orense province. Jose Vincente Casado, from Leon, and other dealers, had specimens at the Bilbao and Barcelona shows.

The fluorite mines in Asturias province have contributed this year with some novelties. In the Moscona mine, yellow transparent barite crystals have been found, up to 3 cm, associated with the well-known yellow fluorite and with calcite crystals. (These specimens were obtained in a relatively small quantity.) In the Jaimina mine, located near the classical Berbes locality, pale blue and violet cubic crystals, up to 10 cm have been found. The crystals have an irregular distribution of the color, not the usual zonation parallel to the faces of cube.

The La Union-Cartagena area is usually a prolific producer of specimens, but this year no substantial novelties appeared. Dealers from the area have the usual blue barites and the specimens of acicular gypsum crystals from San Timoteo mine. Gypsum has also been found in the "El Paraiso de Klein" mine, near Pulpi, but actually located in the municipio of Pilaf de Jaravia, Valencia province. Transparent crystals up to 10 cm have been found. Associated with them are celestite needles, in some specimens as inclusion in the gypsum crystals.

The Eugui quarry is well known for its magnificent dolomite specimens. However, magnesite is rarely found as crystals. This year, Pedro Echevarria, from Pamplona, obtained a reasonable suite of specimens, with lenticular magnesite crystals protruding from massive magnesite. And speaking of Eugui, in the Barcelona show Jordi Fabre had a large, fine dolomite specimen with crystals up to 7 cm scattered in matrix; these crystals have the rhombohedron heavily modified by other faces.

From outside of Spain, the most eyecatching specimens seen lately are the large amethyst druses, up to half a meter, from Mina Ayoreita, Rincon del Tigre, Santa Cruz province, Bolivia. In the Barcelona show, Intan S.L., owners of the mine, had a large selection of druses and loose crystals. Individual crystals are up to 10 cm, but the color is usually pale and irregularly distributed, and the crystal faces are lusterless.

Also interesting are the "laden" quartz from Dara Ismael Khan district, Waziristan, Pakistan. Miro, a French dealer, had specimens with crystals up to 10 cm. Luis Miguel Fernandez had green fluorites from Melchor Muzquiz, Coahuila, Mexico.
COPYRIGHT 1999 The Mineralogical, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1999 Gale, Cengage Learning. All rights reserved.

 
Article Details
Printer friendly Cite/link Email Feedback
Title Annotation:What's New in Minerals
Author:Calvo, Miguel
Publication:The Mineralogical Record
Date:Mar 1, 1999
Words:1022
Previous Article:Munich Show 1998.
Next Article:The IMA Commission on New Minerals and Mineral Names: Procedures and Guidelines on Mineral Nomenclature 1998.
Topics:

Terms of use | Privacy policy | Copyright © 2018 Farlex, Inc. | Feedback | For webmasters