Science

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. 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. 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. 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 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!