Meet Dr. Chris Osterman: View, Learn & Purchase Specimens from a Once-in-a-lifetime Native Silver Discovery at the 2026 RMGM Tucson Mineral & Fossil Show

Meet Dr. Chris Osterman: View, Learn & Purchase Specimens from a Once-in-a-lifetime Native Silver Discovery at the 2026 RMGM Tucson Mineral & Fossil Show
By Rachel Ford

​At the 2026 RMGM Tucson Mineral & Fossil Show, collectors and mineral enthusiasts will have the rare opportunity to witness one of the most extraordinary native silver discoveries ever documented. Dr. Chris Osterman will present his findings from a modern rediscovery of Arizona’s legendary silver heritage, which bridges deep geological history, frontier lore, and cutting-edge mineral exploration.

Dr. Chris Osterman’s path to this discovery is grounded in rigorous science and decades of field experience. Trained initially as a mining engineer (BSc Mining Engineering -  U of Idaho), Osterman went on to earn advanced degrees (MSc Geological Engineering - U of Arizona) in geology, culminating in a PhD in Geology from the Colorado School of Mines, focusing on sediment-hosted copper deposits in Namibia. His career, spanning over 30 years, has been defined by a rare combination of technical expertise and an instinct for identifying geological anomalies that others might overlook.

That instinct led him to Globe, Arizona, after a friend tipped him off to unusual silver finds in the area around 2019. What began as scattered reports from a group of metal detectorists quickly evolved into one of the most significant native silver discoveries of the modern era. The first breakthrough came when some local metal detectorists uncovered a 16-pound native silver nugget affectionately nicknamed “The Sweet Potato.” This initial rediscovery confirmed suspicions that something extraordinary lay beneath the surface.

Over the following two years, nearly 200 pounds of native silver were recovered in roughly two dozen pieces, ranging from a few grams to astonishing specimens weighing up to 120 pounds. Recognizing the significance of the find, a deal was struck to purchase and stake a claim to the property. The local metal detectorists, uninterested in traditional lode mining, stepped aside, clearing the way for what would become known as the 417 Project, named after the largest nugget ultimately recovered.

The project’s primary goal was ambitious and clear: to locate the source vein—the long-sought “motherlode” responsible for these massive silver deposits.

Record-Breaking Native Silver Specimens

The silver recovered from the 417 Project is remarkable not only for its size, but for its form. These are not delicate wire silvers, but massive, crystalline native silver nuggets, often associated with smoky quartz. Among the most notable specimens:

• 417.8 lb nugget – the largest intact native silver nugget known in the world
• 116 lb nugget
• 86 lb nugget, split down the middle, widely regarded as the most visually striking due to its crystalline structure and classic silver appearance​

The 86-pound split specimen, in particular, shows silver tarnish on the exterior while retaining remarkable internal luster. Collectively, these specimens redefine what many believed possible for native silver formation. Dr. Osterman has described the discovery succinctly: “It’s a one-in-a-billion chance of finding something like this. It is very unique, it’s just not found.”

To enhance the silver’s natural luster, the specimens were professionally treated by Brian Lees using hydrofluoric acid, a specialized process that removes surface oxidation and reveals the metal's brilliance. Since then, many of the largest nuggets from the 417 Project have been on loan to the University of Arizona’s Alfie Norville Gem & Mineral Museum, where they have drawn significant attention from both scientists and the public.

​For the 2026 RMGM Tucson Show, Dr. Osterman will debut newly fabricated custom display stands, allowing these specimens to be exhibited and offered for sale in a show setting for the first time. In addition to the museum-grade pieces, approximately 200 native silver nuggets from the discovery will be available, along with over 200 lapidary slabs cut from the silver, cabochons, freeform polished nuggets, and jewelry crafted directly from the discovery, featuring set cabochons and natural silver forms.

Globe, Arizona: Silver Legends Reawakened

The discovery also reconnects Globe to its origins as a silver district. Historical accounts suggest that 500-pound silver nuggets were discovered in the area in the late 19th century, though many were smelted down and lost to history. Local legend holds that Apaches were among the first to work native silver in the region during the 1870s, smelting it to make bullets, an origin story often cited as the root of the “silver bullet” legend later popularized in American folklore.

The Richmond Basin, part of the broader Arizona Silver Belt, played a critical role in this history. Early prospectors followed alluvial silver washes upstream to locate lode deposits, establishing mines such as McMorris, La Plata, Helena, and Silver Sevens. As silver prices declined and copper rose to dominance, many of these high-grade silver districts were abandoned, until now.

​The Search Continues… Although the property was sold approximately two years ago to Silver One Resources, whose exploration focus is on massive silver deposits, the 417 Project's mission continues. The ultimate objective is still the same: to fully define and understand the source vein responsible for one of the most significant native silver discoveries ever recorded.

For collectors, historians, and geologists alike, the 417 Project is more than a find; it is a rediscovery of Arizona’s silver legacy, brought vividly back to life.

See the world-record native silver specimens of the 417 Project in person at the 2026 RMGM Tucson Mineral & Fossil Show. You can find Chris and his specimens at his booth “Ore Décor” #39 in the “Tent Show” of the RMGM Tucson Mineral & Fossil Show. 

The show will be open daily from 10-6 from January 30 to February 14, 2026, with an early closing of 4 pm on the final day (2/14). The RMGM Tucson Mineral and Fossil Show is located at 1920 N. Oracle Rd. in the “Mineral District” of the Tucson Gem & Mineral Showcase. Admission to the show and plentiful on-site parking are free. The show is open for both retail and wholesale transactions, and food trucks will be on-site. As with any RMGM Promotions show, the atmosphere is family-friendly and focused on quality mineral and fossil dealers from around the globe.