Wulfenite Specimens Prepared for Spotlight at the Tucson Show

Rice NW Museum is getting prepped and ready to exhibit at the Tucson Gem and Mineral Show in February. In keeping with the show’s theme this year, the Rice NW Museum will be displaying some of its finest wulfenite specimens. Curator Julian Gray began planning the case layout months ago, and he has been working with volunteer Angela Piller to prepare. They teamed up to assess which specimens can travel safely, which ones look best next to each other, and which pieces tell a compelling story on display.

Curator Julian Gray, left and volunteer Angela Piller chose the wulfenite specimens for travel

The museum has more than a dozen top wulfenite specimens, in a surprising variety of colors and shapes. If you’re not familiar with this mineral, wulfenite is a lead molybdate, with a chemical formula of PbMoO4. Unlike other lead or molybdenum minerals, which are usually gray, wulfenite can be orange, yellow, red, and other colors. Wulfenite most commonly forms in thin, square crystals that are sometimes quite lustrous. According to Mindat.org, wulfenite is “a secondary mineral typically found as thin tabular crystals with a bright orange-red, yellow-orange, yellow or yellowish grey color in the oxidized zones of hydrothermal lead deposits.” Primary minerals are generally sulfide minerals like pyrite (iron sulfide) or galena (lead sulfide). Corrosive ground water reacts with primary minerals forming new, more exotic secondary minerals such as wulfenite, which is highly sought by mineral collectors.

Wulfenite occurs in a variety of colors, and was a great choice for this year’s show theme.

To prepare for the move, the curating team donned their protective gloves and got to work. They removed top candidates from the display case in the Main Gallery and assembled the proposed display on a table, where they could mix and match and evaluate specimen heights and sizes. Once they were satisfied with the plan, they began boxing up the materials carefully with bubble-wrap and other precautions for the move.

Packaging for the move is an important consideration; some of the best specimens were judged too fragile to transport and will remain on display.

The final step is to carefully shift around the remaining specimens in the case to avoid any obvious holes. Keen-eyed visitors who know the collection intimately will spot the changes, but some of the top specimens in the collection are deemed too fragile to move and won’t be making the trip.

The final step is to rearrange the specimens still on display to avoid obvious gaps or holes.

The specimens will return and be back on display by the end of February.

Tucson is one of the most exciting times of year and places to go shopping for the museum collection and new museum store stock, so stay tuned to see what new acquisitions Julian brings back!

What’s in the Box: You’re ripped, Eurypterid!

Just back from Tucson, this little fellow is an extinct critter called a eurypterid. It’s one of the acquisitions from this year’s enormous Tucson Gem & Mineral Show, where we join other national and international museums annually to show off our specimens, make new purchases, and talk shop.

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The long tail spike has led some to call the eurypterid a “sea scorpion,” though we don’t know whether it was venomous. This specimen has one of two distinctive paddle-like arms remaining, and the frilly appendages sprouting off the head are its walking feet. These creatures lived in Silurian seas over 415 million years ago.

This specimen is headed to a box for now, but we should be putting it out on display before long! Anyone have any good ideas for a nice nickname?

What’s in the Box? Quicksilver

Halloween has passed, but the scares continue with this slippery substance: mercury! The faded label on this vial, acquired in a recent donation, says, “Mercury from thermometer.” Inside, a silver blob bounces back and forth when the vial is shaken. But what is this toxic liquid doing in a blog post from a mineral museum?

Mercury in vial

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What’s in the Box? Old Familiar Places

The outdoorsy among us who have spent time in the Seattle area are surely familiar with Mount Si, a popular hiking destination close to the city. But did you know that Mount Si hosts beautiful minerals as well as incredible views?

Quartz with dravite

This specimen is on its way back to the box after three months on display in the Washington County Museum in Hillsboro, OR. It is a plate of quartz crystals covered with dravite tourmaline from the Bald Hornet claims on Mount Si in Washington state.

The Bald Hornet claims were developed in the aftermath of the 1869 discovery of iron ore in the Snoqualmie Pass area. While these small-time claims did not manage to produce any economic ores, they did give us crystallized mineral specimens like these. Such specimens are generally associated with contact zones, where intrusive granitic rocks interacted with surrounding sedimentary rock, especially limestone.

(Mining claim information sourced from “Discovering Washington’s Historic Mines (Vol. 1)”, ed. Ina Chang.)

This post is part of our What’s in the Box? series.

What’s In The Box? A Light in the Dark

You’ll almost never see gorgeous red realgar crystals on display, and if you do, it won’t be for long. Why? It turns out that realgar is one of several minerals that changes and degrades when exposed to light.

Realgar crystal

Realgar from Shimen, Changde Prefecture, Hunan, China

If left on display, this light-sensitive crystal would begin to turn dark and eventually change into an entirely different mineral: the powdery orange pararealgar, shown below. This happens because of the energy carried in certain wavelengths of light. When that energy hits atoms in the crystal, it causes some of their atomic bonds to break and rearrange into a different structure. For this reason, realgar is one mineral that will always stay inside the box!

Pararealgar crystals

Pararealgar from Royal Reward Mine, King County, Washington, USA

Even common minerals like amethyst and fluorite can begin to fade over time, especially if exposed to bright sunlight for long periods. We recommend displaying your treasures on a shelf rather than a windowsill.

This post is part of our What’s in the Box? series.