MINERALOGY

2025-08-20T18:07:00.001-05:00

Recomiendo ampliamente esta pagina para Ciencia y Exploracion Geologica del Ing. Geologo Luis Perez:

Washing my collection of minerals

2021-01-01T11:08:00.009-06:00

I took advantage of being on vacation to wash my collection of mineral the week of December 21st, 2020. I enjoyed washing one at a time with a tooth brush and hand soap, the results are unbelievable, as they shine like saying thanks for the well deserved shower. I cleaned their display, and I also got a new LD lamp much more powerful than the previous "candle" they had. I am proud of the hard work, it pays off in the end. I will share some of the pictures, and feel free to share if you enjoy this as much, or is it just me. Happy new year 2021.

Colored diamonds? Diamonds are not forever anymore!

2017-01-24T13:05:00.003-06:00

Ever since I was a kid I remember the first time I saw a diamond, it was a jewelry store in Guadalajara, Mexico. Lived there until I started college in Mexico city in the mid 70's. My Mom explained to me that day that diamonds were very shiny, durable, that one can cut glass of a window with this the hardest natural substance and those features made it very expensive; and because of the clarity, and purity, this was a typical stone for women when they got engaged, and so forth. I think this was a good Geology class that started to give me my professional direction. So, the picture I had in my life for years about diamonds, was that the diamond was color-less, with a mega high refraction index, mounted on rings, earrings, or pendants, and that they were forever, very famous even in 007 movies. Once on college, I had the chance to see the first specimen, an hexoctahedron in my Mineralogy class brought to the classroom by my professor, famous Mexican Petrologist Raul Ortiz Asiain. A few days ago (40 years later), I was walking down one of the floors of the worldwide famous The Galleria Mall when I stopped by The Debeers, and I realized that the color-less are almost a thing of the past, nowadays the trend is to look for colored diamonds! I was flabbergasted! some look like topaz, or citrine, but not like diamonds. The blue ones look like a shiny topaz, or even an aquamarine, if it wasn't for its refraction, they would've fooled me. I was very disappointed, and I firmly believe that diamonds are not forever anymore! I am not even sure the colored specimens have some fake color lab-made. Didn't mean to get off on a rant, but I said it. Diamonds are diamonds, fantastic and almost perfect even in its crystallography, pursuing a sphere. Happy day my dear readers.

Minas Gerais Brazil's specimens display in the Intercontinental Hotel in Mexico city!

2015-09-25T18:29:00.003-05:00

Color of amethyst geodes is very similar to the color of a Malbec wine

2014-05-26T21:31:00.002-05:00

Amazing surprise checking in at the Intercontinental hotel in Mexico City by Reforma (Campos Eliseos). My breath was taken away when I saw this beautiful 1.5 m specimen, a gorgeous amethyst geode from Minas Geraes, Brazil in the lobby. It seems to me that they were waiting for my arrival. I immediately took my camera and captured several pictures, which I believe some came up good, I hope you enjoy my selections. To celebrate, nothing better than an amethyst colored Malbec wine from Mendoza, Argentina 2010 crop.

What's new in the mineral world?

2014-05-26T09:26:00.000-05:00

Tom's online report 37 (Spring 2014)

Click the following text to enter Tom's online report:

Rob Lavinsky’s The Arkenstone site (irocks.com) has undergone a complete redesign, and its new incarnation, like the old one, has very “deep” galleries loaded with fine specimens, fine Joe Budd photos of same, and much documentary information. Among Rob’s post-Tucson updates on the new site is a section which offers specimens from the Herb Obodda collection—heavy on old European classics and on more recent things from Herb’s former stomping........

Keynote Speaker at the Society of Women in the Petroleum Industry Houston

2014-02-14T16:13:00.001-06:00

What a privilege to speak at the SPWP on February 13, 2014 early in the morning with a nice breakfast consisting of French toast, bacon, coffee and orange juice. Almost 70 women of the Petroleum Industry in Houston from petroleum engineers Halliburton to owners of successful companies supplying the industry. and female NOV colleagues, one of them is the Executive VP for the SPWP.

My presentation was about Geology Applied to the Oil & Gas Sector. Feedback has been good, and I look forward to a future part II meeting. There was just one Geologist in the audience, and therefore I decided to put some slides together to give them a crash course in Geology from the rock cycle to tectonic plates and Earth's time table. I had been their keynote speaker before: 1995. Time flies (a friend of mine says, he is a pilot). I truly enjoyed it. The picture is a nice gift now being shoed off in my office. Happy Valentine Day!

Amazing crystals from the Tucson Gem & Mineral Show 2013

2013-12-01T20:04:00.001-06:00

In order, the following beauties: Native Gold dendrites on Quartz crystal matrix! From Rosia Montana, Verespatak, Alba County, Romania | Brochantite acicular crystals on Limonite coated Quartz! From the Blanchard Mine, Bingham, Hansonburg District, Socorro Co., New Mexico | Kämmererite (Chromian Clinochlore) on matrix From the Kop Krom mine, Kop Daglari, Erzurum Province, Eastern Anatolia Region, Turkey | Sphalerite sitting atop Chert with Chalcopyrite From the Ballard Mine, Baxter Springs, Picher Field, Cherokee County, Kansas | Forsterite var Peridot From Sapat Gali, Naran-Kaghan Valley, N.W.F.P., Pakistan | Aquamarine crystals and Muscovite From Chumar Bakhoor, Hunza Valley, Gilgit District, Gilgit-Baltistan, Pakistan | Fluorite cubes set against a drusy Quartz matrix From the Blanchard Mine, Bingham, Hansonburg District, Socorro County, New Mexico | Aquamarine with Schorl Tourmaline on Albite matrix From Erongo Mountain, Erongo Region, Namibia | Sphalerite sitting atop Chert with Chalcopyrite! From the Ballard Mine, Baxter Springs, Picher Field, Cherokee County, Kansas Rhodochrosite with purple Fluorite on needle Quartz From the Four Ball Pocket, Fluorite Raise, Sweet Home Mine, Alma, Park County, Colorado | Rhodochrosite with purple Fluorite on needle Quartz From the Four Ball Pocket, Fluorite Raise, Sweet Home Mine, Alma, Park County, ColoradoSpecimens to take our breath away! My apologies if this text looks clumsy, my suggestion is for you to print it, it will be easier. Enjoy them! November 2013.

What is each specimen? Beautiful pictures from the Museum of Science in Dallas

2013-09-28T20:29:00.001-05:00

What a beautiful collection of crystals, and also rock formations, crevices models, and even the architecture of the Museum looks like a twin topaz! Below is my new post of pictures taken there, in the heart of Downtown Dallas, the Ross Perot (former Presidential candidate in the USA). Name the crystals! I will have to make another visit to the area, as I just saw half of it, as it was already late when I made it. The specimens go from Schellited to tourmaline, beryl, wulfenite, native gold, gypsum, etc. Enjoy them, I took my iPhone 4S to work hard.

Tempting & expensive hobby! Minerals from the Gem & Mineral Fine show in Houston, TX - April 2013

2013-04-27T19:17:00.001-05:00

Rare minerals, others not so much, all beautiful though!

2013-02-09T12:47:00.003-06:00

There is a new mineral name I discover frequently, so, I am happy to share some of those hereby. Thanks to Kristalle for offering these specimens since 1971

Oranges? no, Cacoxenite, as seen through a microscope 18x

2012-10-27T09:10:00.004-05:00

Formula:

Al (PO

)

(OH)

· 17H

Name:	From the Greek κακός for "bad" and ξένος for "guest" due to the fact that the phosphorous content of cacoxenite lessens the quality of iron smelted from ore containing it.
System:	Hexagonal
Colour:	Yellow to brownish ...
Type Locality:	Hrbek Mine, Svatá Dobrotivá (St Benigna), Beroun (Beraun), Central Bohemia Region, Bohemia (Böhmen; Boehmen), Czech Republic \| This particular one from La Paloma, Spain
Year of Discovery:	1825
Geological Setting:	Common accessory mineral in oxidation zone of magnetic and limonite iron ores, novaculites, rarely in iron rich sediments and soils.
Luster:	Silky
Diaphaneity (Transparency):	Translucent
Colour:	Yellow to brownish yellow, reddish orange, golden yellow, deep orange, green; yellow in transmitted light
Hardness (Mohs):	4-Mar
Density	2.2 - 2.6 g/cm³
Crystal System:	Hexagonal
Class (H-M):	6/m - Di-pyramidal
Morphology:	Crystals crudely hexagonal, acicular [0001], with a hexagonal cross section at times and indistinct pyramidal faces. Commonly in compact, concentric, spherical to radial aggregates. In bundles, randomly fibrous; as coatings or inter-granular cement.

2012-04-20T13:32:00.001-05:00

Volcanic and Geological Resources

There are over 500 documented volcanos on Earth. Just about every culture has some reference to these fantastic natural events; in fact, the word “volcano” comes from Vulcan, the Roman God of Fire and Metalworking (Volcanoes). As society progressed, people began to understand volcanoes as more than just gateways to hell and internal suffering, and instead recognize them as the result of tectonic plate boundaries and shifting.

Below you’ll find a collection of resources centered around volcanoes and geology from around our world and the planets closest to us. Many of these resources are products of geology departments at various different universities, and feature a wide range of information in addition to the resources listed. Image courtesy of Wikimedia Commons.

Glossary of Volcanic and Geologic Terms – The most extensive glossary on the web. Presented by Oregon State University, this list covers all the basic terms and all the un-basic terms as well.

How Volcanos Work – If you need a refresher course, this website is a comprehensive educational resource that describes the science behind both volcanoes and the volcanic processes.

Hawaiian Volcano Observatory – From the United States Geological Survey, this site takes an in-depth look at the many volcanos and earthquakes on the Hawaiian islands, including fantastic images and extensive fact sheets.

Volcanic Activity in Iceland – A comprehensive overview of the volcanos in Iceland, including a gallery of images and a video of the Fimmvörđuháls volcano erupting in Southern Iceland.

Physical Geology Slides-Volcanoes – A great collection of images, categorized by type with descriptions. Includes cinder cones, stratovolcanoes, calderas, and images of Vesuvius and Pompeii.

Volcano and Earthquake Resources on the World Wide Web – Though an older site, this page from Colby College contains live links to some fantastic volcano and geographic links from around the net, including observatory homepages and earthquake information in the U.S. by region.

Virtual Geology – This site features virtual field trips, regional geology, as well as some truly incredible images of geology and scenery from around the world.

A Geological Guidebook to Dante’s Peak – A humorous rendition of the movie Dante’s Peak as told by a geologist horrified by the inaccuracies of the film who feels the need to set the record straight about volcanos.

Volcanoes on Venus – From Oregon State University, this webpage features an overview of volcanoes on Venus, as well as images of Venus’ large shield volcanoes, lava flow features, and some remarkably unusual volcanoes as well.

Exciting Science: Life at the Extremes – Microbiology of deep-sea volcanoes – Rutgers University presents a fascinating look at the life that consists in water as hot as 400°C, extremely high pressures, and surrounded by high concentrations of hydrogen sulfide.

Submarine Volcanoes – This article contains a thorough explanation of submarine volcanoes’ plate tectonic settings, submarine eruptions, evidence of features and deposits, and is supplemented by several images.

Geology of Mars – This site has information and images of many global features on the planet of Mars, including volcanoes, craters, landslides, tectonic plates, and wind mechanics.

Video of Sand Volcano (injectite) Erupting – This video, taken in Saudi Arabia, shows an injectite volcano exploding right next to a busy street.

Michigan Technological University Volcanoes Page – This site, sponsored by the Keweenaw Volcano Observatory, includes an extensive variety of links to all things related to volcanos, including a section of volcano jokes and recipes for cooking with lava.

The Volcano Information Center – From the University of California at Santa Barbara, this site “provides links to websites that are resources for data and to inform the user about general volcanology, including features of volcanoes, volcanic eruptions and volcanic hazards.”

Hawaii Volcanism: Lava Forms – This page includes a brief but thorough explanation of different types and behaviors of lava and includes several pictures of lava from the Hawaii volcanoes.

Volcanoes of Canada and the western USA – Each region of Canada and western United States features a map of where the volcanoes are, as well as a complete list of the documented volcanoes, their type, and activity status.

Courtesy of: http://www.onlinecollegeclasses.com/

Minerals to fall in love with Mother Nature!

2012-02-18T14:40:00.003-06:00

A little bit more minerals, not lees amazing!

2012-01-20T17:36:00.000-06:00

Sapphire, pyrrhotite, wulfenite, pyromorphite, aquamarine, zircon, calcite, morganite, polibasyte and proustite, tourmaline, fluorite, scheelite! simply awsome!

2011-11-20T19:41:00.001-06:00

Topaz, Scheelite, Fluorite, Pyrrhotite, Copper, Silver, Millerite from Spain to Pakistan, Russia, Mexico and Michigan! to take your breath away!

2011-09-03T10:50:00.001-05:00

From top to bottom:
Topaz in Calcite matrix - From Katlang, Mardan District, Northwest Frontier Province, Pakistan. Scheelite set with Quartz on matrix - From the Gharmung Area, Skardu District, Baltistan, Northern Areas of Pakistan.
Fluorite with blades of white Barite - From Berbes, Berbes Mining Area, Ribadesella, Asturias, Spain.
Acanthite and curling Native Silver wires - From the Reyes Mine in Guanajuato, Mexico.
Pyrrhotites on Quartz crystals - From the Nikolaevskiy Mine, Dal'negorsk, Primorskiy Kray, Russia.
Native Copper - From the Calumet & Hecla Mine, Calumet, Houghton County, Michigan.
Botryoidal Chalcedony and fine Millerite crystals - From Halls Gap, Lincoln County, Kentucky.
Red Beryl crystals in and atop Rhyolite matrix - From the Wah Wah Mountains near Delta, Utah.
Boleite with Calcite on hand matrix - From Boleo, Baja California, Mexico.

Bloody minerals shouldn't be a bad word in UK, some as this red!

2011-06-30T22:01:00.008-05:00

Legrandite and Adamite from the famous Ojuela Mine in Mapimi, Durango Mexico, and of quartz... many more

2011-06-04T21:15:00.018-05:00

Monoclinic prismatic Legrandite crystals with Limonite matrix From the Ojuela Mine in Mapimi, Durango, Mexico - Zn2(AsO4)(OH)•(H2O) - Named after the Belgian mining engineer, Legrande.

Trigonal hexagonal scalenohedral Rhodochrosite in cluster on Quartz crystals from the Hedgehog Pocket, Main Stope Drift, Sweet Home Mine, Alma, Colorado - MnCO3 - From the Greek rhodon -"rose" and chroma - "color."

Hexagonal dihexagonal dipyramidal Beryl var. Aquamarine crystal with tourmaline Schorl rom the Erongo Mine, Namibia, SW Africa - Be3Al2Si6O18 - From the ancient Greek, beryllos, signifying a "precious blue-green color of sea water" stone.

Orthorhombic dipyramidal Barite crystal on reddish Hematite & Dolomite covered matrix from Frizington, West Cumberland Iron Field, North and Western Region (Cumberland), Cumbria, England - BaSO4 - From the Greek, baryos, "heavy."

Trigonal ditrigonal pyramidal Pyrargyrite crystals on top of Calcite rhombs from the Samson Mine, St. Andreasberg, Harz, Germany - Ag3SbS3 - From the Samson Mine, St. Andreasberg, Harz, Germany. From the Greek, pyr and argyros, "fire-silver" in allusion to color and silver content.

Orthorhombic dipyramidal Forsterite var. Peridot on Magnetite from Sapat Gali, Naran-Kagan Valley, Kohistan District, North-West Frontier Province, Pakistan - Mg2(SiO4) -
Named for Johann Forster, German naturalist.

Orthorhombic dipyramidal Adamite clusters on Limonite from the Ojuela Mine, Mapimí, Durango, Mexico - Zn2(AsO4)(OH) - Named after the French mineralogist Gilbert Joseph Adam (1795-1881).

Rhodochrosite, Calcite, Scheelite, Spessartine, Pyrrhotite, Millerite, and more all together in one post!

2011-05-19T18:06:00.008-05:00

In order of appearance from the top down:

Rhombs of Rhodochrosite atop Tetrahedrite and Quartz matrix! From the Sweet Home Mine, Alma, Park County, Colorado.
Measures 3.1 cm by 3 cm by 3.5 cm in total size.

Twinned Golden Calcite with Sphalerite on matrix! From the Denton Mine, Harris Creek District, Hardin County, Illinois.
Measures 7 cm by 7.2 cm by 5.2 cm in total size.

Scheelite crystal with glassy Adularia! From Mt Xuebaoding, Pingwu Co., Mianyang Prefecture, Sichuan Province of China. Measures 7.3 cm by 5.5 cm by 4.4 cm in total size.

Spessartine Garnet with dark botryoidal Goethite! From Tongbei, Yunxiao Co., Zhangzhou Prefecture, Fujian Province, China.
Measures 12.5 cm by 10.2 cm in size.

Large pyramidal Pyrrhotites on Quartz crystals! From the Nikolaevskiy Mine, Dal'negorsk, Primorskiy Kray, Russia.
Measures 7 cm by 12.6 cm by 10 cm in total size.

Cavern of botryoidal Chalcedony and fine Millerite crystals! From Halls Gap, Lincoln County, Kentucky.
Measures 7.2 cm by 11 cm by 6.8 cm in size.

Lustrous crystals of Pyrargyrite nestled between brown Calcite crystals and casts!From Level 630 of the San Guillermo Vein, San Luis Shaft, Fresnillo, Zacatecas, Mexico.
Measures 3 cm by 4.5 cm in size.

Combination of Barite and Gypsum crystals on Yellow Calcite! From the Elk Creek locality, Dalzell, Meade County, South Dakota.
Measures 7.5 cm by 15.3 cm by 12.5 cm in size.

Simply Amazing!

If you want to buy beautiful minerals, bring lots of money!

2011-05-14T12:36:00.012-05:00

A good challenge: Walk the aisles of the Tucson Gem and Mineral show, and mentally buy the ones you like! I confess, I spent millions in less than 100 yards wow! Here, in order of appearance: rhodochrosite, emerald, again rhodochrosite, native silver, kunzite, fluorite/barite acanthite, native copper and ruby red beryl. Impressive specimens that adorn the museums and private collections, like that of Rep. Romero de Tehuacan Puebla, a beautiful museum with amazing specimens such as legrandita, adamite, pyrites from Naica, etc. I used to take my students to this museum on an unforgettable journey of two days, after visiting the museum, Dr. Romero used to take us to a tour around his state of the art chicken farm. I lost track of my students, and obviously of the Mineral Museum of Tehuacan, unique in Mexico at least in the 80's, of course, the Deputy Romero died a few years ago.

In a recent visit I did to a gem & mineral show in Houston, I saw specimens worth almost $100,000 USD, I could not believe it. That inspired my title of this post. May 2011

Fluorite lego? No, actual crystals directly from Mother Nature

2011-03-27T13:35:00.008-05:00

From various locations, in its amazing variety of colors and habits, Fluorite is a fantastic mineral. Let me start from a location I visited for several months, such as Naica, Chihuahua in Northern Mexico whose location is off the "Panamerican Freeway" between Camargo and Delicias. From this mine, fluorite and other beautiful crystals have been collected, and it became world famous for its recently discovered giant gypsum crystals cave. Naica produced unique crystals of fluorite that vary from a very pale pink to almost transparent specimens with pyrite crystals inside, some of these in my private collection. I worked in this mine while I was still in College back in the late 70's, and to tell you the truth, I really enjoyed it, as I was assistant of the most prominent Mineralogist in Mexico Dr Raul Ortiz Asiain, and my passion for minerals was already there.

Also, pictures of fluorite from Pointe Kurz (3600 m altitude), Mont Blanc Massif, Haute-Savoie, France, and finally from Caldera 3, Mina Moscona, Solís, Corvera, Asturias Spain

Fluorite:

Chemical Formula: CaF2
Composition: Molecular Weight = 78.07 gm
Calcium 51.33 % Ca 71.83 % CaO
Fluorine 48.67 % F 48.67 % F
Environment: Low temperature vein deposits
Crystal System: Isometric - HexoctahedralH-M Symbol
Cleavage: {111} Perfect, {111} Perfect, {111} Perfect
Color: White, Yellow, Green, Red, Blue.
Density: 3.01 - 3.25, Average = 3.13
Diaphaneity: Transparent to subtranslucent
Fracture: Uneven - Flat surfaces (not cleavage) fractured in an uneven pattern.
Habit: Crystalline - Coarse - Occurs as well-formed coarse sized crystals.
Habit: Disseminated - Occurs in small, distinct particles dispersed in matrix.
Habit: Massive - Granular - Common texture observed in granite and other igneous rock.
Hardness: 4 - Fluorite
Luminescence: Fluorescent, Short UV=blue, Long UV=blue.
Luster: Vitreous (Glassy)
Streak: White

Lead vanadate forms Vanadinite, discovered in Mexico

2010-09-01T21:33:00.002-05:00

Mine: San Carlos (Mina Apex), San Carlos, Manuel Benavides, Chihuahua Mexico
Pb5(VO4)3Cl

Vanadinite is an uncommon mineral, only occurring as the result of chemical alterations to a pre-existing material. It is therefore known as a secondary mineral. It is found in arid climates and forms by oxidation of primary lead minerals. Vanadinite is especially found in association with the lead sulfide, galena. Other associated minerals include wulfenite, limonite, and barite.[2][4][5]

It was originally discovered in Mexico by the Spanish mineralogist Andrés Manuel del Río in 1801. He called the mineral "brown lead" and asserted that it contained a new element, which he first named pancromium and later, erythronium. However, he was later led to believe that this was not a new element but merely an impure form of chromium. In 1830, Nils Gabriel Sefström discovered a new element, which he named vanadium. It was later revealed that this was identical to the metal discovered earlier by Andrés Manuel del Río. Del Río's "brown lead" was also rediscovered, in 1838 in Zimapan, Hidalgo, Mexico, and was named vanadinite due its high vanadium content. Other names that have since been given to vanadinite are johnstonite and lead vanadate.

Along with carnotite and roscoelite, vanadinite is one of the main industrial ores of the element vanadium, which can be extracted by roasting and smelting. It is occasionally used as a source of lead. A common process for extracting the vanadium begins with the heating of vanadinite with salt (NaCl) or sodium carbonate (Na2CO3) at about 850°C to produce sodium vanadate (NaVO3). This is dissolved in water and then treated with ammonium chloride to give an orange coloured precipitate of ammonium metavanadate. This is then melted to form a crude form of vanadium pentoxide (V2O5). Reduction of vanadium pentoxide with calcium gives pure vanadium.

Sources: WEikipedia and the University of life!

Featured blog

2010-05-03T08:50:00.001-05:00

Blog award

I am sad seeing these beauties in women's rings / collars!

2010-04-17T11:06:00.011-05:00

In order of appearance:

Tourmalines on Cleavelandite blades from the Himalaya Mine, Mesa Grande District, San Diego County, California

Linarite from the Grand Reef Mine in Graham County, Arizona

Prousite sitting atop a Polybasite cluster from the Uchucchacua Mine, Oyon Province, Lima Department, Peru.

Tourmaline from the 1974 Pocket, Tourmaline Queen Mine, San Diego County, California

Galena from the Tsumeb Mine in Tsumeb, Namibia, SW Africa.

Adamite from the Ojuela mine in Mapimi, Durango Mexico