Product · Magnetometers
Geometrics G-856AX Proton Precession Magnetometer
A classic backpack-portable proton precession magnetometer long used for base-station and reconnaissance magnetic survey, and a common find on the refurbished and surplus market.
New Refurbished Absolute Certified Surplus
About the Geometrics G-856AX Proton Precession Magnetometer
The G-856AX is a long-running proton precession magnetometer design from Geometrics, historically one of the most widely deployed field magnetometers for mineral exploration, archaeology, and engineering geophysics. Its robust, no-drift proton precession sensor made it a dependable base-station and roving instrument for decades.
While newer Overhauser and cesium systems have largely superseded it for high-throughput survey work, many G-856AX units remain in active service or available as Refurbished and Surplus units — a cost-effective entry point for base-station duty or teaching use.
| Specification | Value |
|---|---|
| Sensor type | Proton precession |
| Sensitivity | ~0.1–1 nT (typical for proton systems) |
| Configuration | Base station or roving |
| Display | Digital readout console |
| Typical use | Base station, teaching, reconnaissance survey |
| Market position | Legacy design, common in Refurbished/Surplus |
Available across all four PartnerGeometrics condition tiers — New, Refurbished, Absolute Certified, and Surplus. See our condition tier guide for details on what each tier includes.