Product · Gravimeters
LaCoste & Romberg Model G Gravimeter
The classic zero-length-spring relative gravimeter dating back to the mid-20th century — the long-serving standard for land gravity survey before electronic Autograv-style instruments, and the direct ancestor of today's Micro-g LaCoste product line.
This model has been discontinued by the manufacturer. PartnerGeometrics sources it through the used and refurbished market — available as Refurbished, Absolute Certified, or Surplus only.
Refurbished Absolute Certified Surplus
About the LaCoste & Romberg Model G Gravimeter
The Model G is a mechanical relative gravimeter built around Lucien LaCoste's zero-length spring principle, first developed by LaCoste & Romberg (the Austin, Texas company whose lineage continues today as Micro-g LaCoste). Readings are taken by manually nulling a beam against the spring tension via a calibrated micrometer screw and optical or electronic null indicator, rather than the automated digital readout of later Autograv-style instruments. Its worldwide measuring range without instrument resetting made it the workhorse of gravity survey for decades, and a substantial population of well-maintained Model G meters remains in active service and calibration-lab use today.
LaCoste & Romberg later merged with Scintrex and, subsequently, with Micro-g Solutions to form Micro-g LaCoste — the manufacturer of the current FG5-X absolute gravimeter and gPhoneX gravity meter also listed in our catalog.
| Specification | Value |
|---|---|
| Sensor | Zero-length spring, mechanical, relative |
| Reading method | Manual null balance via micrometer screw |
| Measuring range | Worldwide, no instrument resetting required |
| Typical use | Land gravity survey, geodesy, reference-station networks |
As a discontinued instrument, the Model G is available from PartnerGeometrics as Refurbished, Absolute Certified, or Surplus only — see our condition tier guide for what each tier includes.