Esoterizona Stones 39

Fluorescent Minerals

The following specimens are a few of those acquired at this year's Tucson gem show.

Fluorescent red calcite on quartz, from Cambokeels Mine, Weardale, England.  According to mindat.org, the mine began operation in 1847, and was mined first for lead, then fluorite until its closure in 1989.  The outer workings still feature an arched stone adit specifically designed for horses - there are some great pictures of this mine out there if you search.

Also with nicely formed and phantomed hexagonal "nailhead" crystals - was being sold as a white light specimen, not advertised as fluorescent. 4"x2"x1.5"

Fluorescent green hyalite opal from Zacatecas, Mexico.  This material is so reactive, the fluorescence is clearly visible even in a brightly lit room.  It also belongs to a rare breed of fluorescent minerals that are considered "daylight fluorescent." This means the opal will appear mostly clear under indoor, incandescent lighting, but viewing the specimen in sunlight provides enough UV to activate the fluorescence and make the opal appear green.

This piece also stood out for the large, greenish-clear nodule of opal right on top of the specimen - the opal from this locality tends to occur more commonly as a coating rather than a standalone "crystal." 3.5"x2"x0.5" (sawcut back)

Close up of the nodule, which has a diameter of roughly 10mm.

Fluorescent yellow scapolite (meionite) from Quebec, Canada, shown under longwave UV.  While this piece didn't have as much scapolite as some (see Esoterizona Stones 31), under shortwave it looked like this:

An unusual quantity of bright blue tremolite is visible along with the scapolite.  This blue has previously been misidentified as diopside.

Same specimen, white light. 3.5"x3"x2"

2016 Tucson Gem & Mineral Show

Pass for the main Gem & Mineral show at the Tucson Convention Center.

The theme of this year's show was "Shades of Blue: Minerals of the World."

Arizona has a wide variety of blue minerals.

The Fluorescent Mineral Society also had a display featuring the numerous red (calcite) and green (willemite) combinations of Franklin & Sterling Hill NJ.

Specimens and set-up courtesy of George V. Polman.

For more details about the display, see polmanminerals.com.

Esoterizona Stones 38

Fluorescent Minerals

Fluorescent calcite from Williamson County, TX.  The bands fluoresce creamy yellow and white (appears more blue in the photos) under short, mid and longwave light.

These fist-sized rocks came from massive boulders unearthed by heavy machinery while clearing a new roadbed.  When cracked open with a sledgehammer, the grimy limestone exterior gave way to the beautiful crystalline banding within.

The fluorescent calcite is also highly phosphorescent.

The banded crystals are even more clear in this piece.

Rockhounding, Texas-style:

Esoterizona Stones 37

Fluorescent Minerals 

Fluorescent minerals from the Tres Hermanas Mountains, Luna Co, NM.

This piece is calcite (white), aragonite (green), and caliche (orange).

Same specimen, white light.

This specimen contains chalcedony and aragonite; both fluoresce green in response to shortwave UV.  Portions of the aragonite also fluoresce yellow-white, and are phosphorescent.  The chalcedony is emdedded in the matrix, upper left.

Same specimen, white light.  The clusters of aragonite crystals make these easy to spot in daylight, but not all of them have strong fluorescent response.

Orange caliche and a green that could be aragonite or also caliche.

Same specimen, white light.

Fossil Hunting in the Texas Hill Country

Looking upstream on Ward's Creek, about 80 miles west of San Antonio.

Downstream - water levels were unusually high following a recent winter storm.

Even so, fossils were still evident in the ledges of the limestone creek bed.

Classified the Glenrose Formation, these creatures date from the Cretaceous Period, about 100 million years ago.

A section of Nerinea sp. fossil still encased with matrix.

Another section of Nerinea, an extinct sea snail with a long, horn-shaped shell.

Known locally as the "Tarpley Tornado Snail."

Tylostoma sp, another extinct marine gastropod.

Cretaceous fossil clam.

The best find of the day was this large plate of fist-sized snail shells.

Blue Quartz

Blue quartz phenocrysts in rhyolite from a highway road-cut near Llano, TX.

Locally the material is known as "llanite," as it is unique to the area.

Snow & Lava in New Mexico

Snowy Sierra Oscura Mountains behind the Carrizozo Malpais, aka Valley of Fires.

The ~5000-year-old lava flow had recently weathered "Blizzard Goliath."

When fire meets ice ...