Innovation and Reliability Since 1980

Corporate Profile

GEM – A History of Innovation and Reliability

GEM has had a long and storied history – starting as Geophysical Electromagnetic Systems, a consulting partnership. The company incorporated in 1980 as GEM Systems, and is now known in industry as GEM Systems.

Formed by Drs. Ivan and Jasna Hrvoic, the company continues to be managed by Dr. Ivan Hrvoic who contributes many years of experience in geophysical instrumentation and electronic design.

In the late 1960’s and early 1970’s, Dr. Hrvoic worked as Senior Research Engineer with Scintrex Ltd. During this time, initial research was conducted into the feasibility and design of a Continuous Reading High Sensitivity Airborne Overhauser Magnetometer.

This work was completed in 1983 through a research grant and led to the first of an innovative series of magnetometer/gradiometer technologies featuring three main physical principles – Proton quantum magnetometer, Overhauser quantum magnetometer, and the optically pumped Potassium quantum magnetometer.

A History of Innovation

GEM celebrated 43 years leading the world of Magnetics in 2023

Commercial success of the GSM-8 Proton Precession magnetometer led to early expansion and creation of the GSM-9 Overhauser, the first pulsed Overhauser magnetometer and the GSM-19 Overhauser memory magnetometer – a joint research effort with Lamontagne Geophysics. GSM-10 and 18 magnetometers were also developed and were received well in the resource exploration market.
The company also developed solutions for other fields, such as UXO, volcanology, earthquake prediction, and engineering and environmental disciplines.

Following expansion in 1987, the company launched the GSM-19. This memory magnetometer combines Overhauser technology with proprietary free-radical solutions and firmware that is also able to accept other geophysical methods such as VLF and multiple gradiometer channels. GEM’s team of engineers have now re-packaged the system and enhanced cycle times while establishing industry benchmarks for low weight, low power consumption and high sensitivity.

As the company’s reputation as a proven supplier of instrumentation for total field measurement grew, they branched into other fields, including the observatory field. Today, Overhauser magnetometers have replaced many of the conventional Proton Precession observatory installations around the world.

The Overhauser and Proton magnetometers/gradiometers continued to see success as they moved into later versions, most notably Version 7 which saw many key design and technical enhancements. These magnetometers continue to be developed – even today – justified by their performance and general acceptance in the earth sciences and other subsurface investigations.

At GEM, we are committed to delivering cutting-edge solutions to our global clientele. As part of our ongoing research programs, we have introduced the groundbreaking Potassium magnetometer. With its remarkable sensitivity of 0.0002 nT and a host of other exceptional features, this magnetometer has emerged as one of the world’s most advanced and effective instruments. It sets a new milestone in data quality, surpassing not only Overhauser and Proton instruments but also competing optically pumped cesium magnetometers. Experience the power and precision of our Potassium magnetometer for unparalleled results. Contact us today to explore how this revolutionary technology can benefit your organization.

GEM Ground Solutions


View of a backpack-mounted walking Gradiometer Overhauser magnetometer. GEM was one of the first companies to use backpack-mounted instruments with walking and integrated GPS features to increase efficiency and convenience of field surveys.

The company has been a leader in providing geophysical instruments for ground surveys based on its Proton, Overhauser and Potassium sensors and systems. GEM systems are reliable. There are stories of mags coming in for repair after 26 years in use!

Some novel developments include the “Walking Mag” – the first magnetometer to provide the operator with the ability to walk continuously while making measurements. This walking mode has increased productivity by 3 to 5 times on the ground since sensor staffs and discrete measurements are no longer required. While this technology has been copied by competitors, GEM remains the originator and developer of the most advanced Walking technologies for magnetometers and gradiometers on the planet today.

Sampling rates delivered by the Overhauser and Potassium systems are suitable for new survey approaches, such as automation. With automation, sensors are mounted on a platform (All-terrain-vehicle, sled, bicycle, or other towed conveyance) and advanced at a rapid rate (5 to 10 km) along the ground surface – resulting in a significant productivity gain for those using one of GEM’s towed carts for instance.

GEM Airborne Solutions

GEM’s first airborne project was a vertical helicopter-borne gradiometer created in co-operation with Urtec Instruments and Geotech. It was based on a simple, yet effective self-oscillating Overhauser system. The company also developed the inexpensive GSM-11 airborne magnetometer that contributed to the commercial success of Terraquest Surveys and H. Ferderber Geophysics.

3-Sensor Helicopter Bird

GEM Pioneered the Three-Sensor Helicopter Bird Three gradients are obtained, including vertical, across track and along track.

With the development of the Potassium system with its ultra-high sensitivity and fast sampling, GEM advanced even further into the airborne realm. Helicopter-borne magnetometers and gradiometers have been developed including a single-sensor magnetometer (GSMP-35A/25A), vertical gradiometer, and the leading three-sensor gradiometer which has been purchased by various organizations around the world.

23b airborne systems

Today GEM Systems are used around the World.

GEM continues to make advances in the sky, including the recently upgraded airborne VLF system which uses a new tilt sensor to increase the accuracy and time in which measurements can be made.

We also continue to work on fixed wing installations using the GSMP-35A/25A and have a number of these installations up and running now. Expertise includes consulting on sensors and positioning as well as noise sources that must be addressed in order to make accurate measurements from a moving platform.

Our newest offerings include;

GEM UAV Solutions

In our most recent development, we are now building sensors and electronics for Unmanned Airborne Vehicles (UAVs) which are becoming increasingly important in a variety of fields for unmanned airborne surveying.

The VLF-EM UAV system designed by GEM Systems.

Core to the UAV business is the new light weight UAV Potassium Magnetometer. GEM has developed several applications which include light weight towed “birds” and fully integrated systems for multi-rotors and mini helicopters.

A Long Term Focus on its Customers

Through its more than four decades of service to the land, airborne and observatory professional community, GEM has continued to seek optimal solutions that will enable its customers to work more cost efficiently and effectively.

In partnership with companies, such as Terraplus Inc., and its network of agents and representatives around the world, GEM thanks its customers and potential customers for their continuing support and input.

Customer input is particularly valued as GEM continues to anticipate strong growth and an ongoing commitment to addressing its customers’ real-world earth science challenges.

Key Players

Some of the key players whom you may end up dealing with at GEM are:

  • Dr. Ivan Hrvoic, the Founder and Chairman of the Board of GEM Systems, is a pioneer in the field of geophysical technology with a distinguished career spanning over four decades. His foundation in scientific knowledge, rooted in his PhD in physics, provided the groundwork for his ground-breaking contributions to the geophysical industry. Dr. Hrvoic’s expertise extends beyond technological innovation to encompass a deep understanding of the challenges faced by geophysical explorers.
  • Doug Hrvoic has been appointed as the new President of GEM Systems. With over two decades of experience, he has a proven track record of success in driving business growth and spearheading innovative product development. Hrvoic’s passion lies in leveraging technology to address real-world challenges. As a recognized authority in magnetic anomaly detection, he has devised cutting-edge solutions for a broad spectrum of applications. As President of GEM Systems, Hrvoic is tasked with steering the company’s expansion and advancement.
  • Michael Wilson, the newly appointed Chief Operating Officer (COO) of GEM Systems. With a unique combination of technical prowess and business acumen, Michael has demonstrated a remarkable ability to foster operational efficiency and drive innovation in the technology sector. At GEM Systems, Michael is responsible for overseeing the company’s day-to-day operational functions, ensuring that all departments work synergistically to achieve the company’s strategic objectives.


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