Geochemical Research and Documentation Assistant GERDA

6.10.2022

Geochemical Research and Documentation Assistant GERDA by MEFFA Lab Oy is an automated tool for analyzing materials. The device gives the possibility to measure samples in a coordinated sequence without having to move the pXRF or VNIR instruments manually. The analyzed material can be drill cores, RC chip samples or soil / base of till samples in sample bags. Furthermore, any flat materials like metals or paintings can be analyzed.

The device is based on a CNC table (Ooznest WorkBee). It can be equipped with a portable XRF (pXRF) analyzer (Olympus Vanta, Bruker S1 Titan/Tracer or SciAps X550) or a portable VNIR spectrometer (Spectral Evolution oreXpress). The unit has a control module based on Raspberry Pi 3 computer and a high-resolution USB camera (Baumer VCXU-65C.R) for taking photos of the measured material. It also features software for easy operation and data processing and visualization. Palsatech’s systems do not have a camera installed as we have separate imaging solutions for samples.

How GERDA works

GERDA is operated on a PC or any gadget with a web browser for the GERDA interface, and it can be attached to a variety of tables. At Palsatech, GERDA is attached to our self-manufactured horizontal drill core logging tables with rollers to help with the handling of sample trays and drill core boxes.

The GERDA system and the operating PC are connected via VPN using GERDA’s integrated Wi-Fi router. After creating a new project on the GERDA interface, it can be divided into several jobs, one job per drill core box for example. The measuring sequence is configured in millimeter coordinates and can be saved for continuous use. Analysis times and other analytical factors can be configured on the pXRF device’s interface, and the GERDA unit does the moving, measuring and data collection from the pXRF device.

The samples can be analyzed straight from the drill core box with certain spacing. The number of analyses per box is 25–35 when using 20 cm measurement point spacing, after which a new box needs to be set up in the system. The measuring depths for the drill core can be automatically calculated by setting the parameters for the measured drill core box shape in the GERDA interface. However, Palsatech’s custom is to measure the measurement point depths by hand to increase accuracy on the depth data.

To make the work more efficient, the samples can also be analyzed by taking measurements from rock discs sawn from the drill core with a clipper rock saw. The discs are sawn at regular intervals from the drill core and are arranged in a continuous sequence on a laser-cut sample tray with space enough for 100–200 samples depending on the core diameter. This reduces the workload from the personnel measuring the samples as the device can run hours without any input from the personnel utilizing the device.

Practical benefits for clients

The GERDA system offers several practical benefits for the clients. It has good maneuverability as it is easy to operate remotely with the Wi-Fi connection between the GERDA system and the operating PC. As the system is automated, there is no need to manually move or hold the pXRF analyzer, which improves the workplace ergonomics.

The system is faster than laboratory analyses and it increases the sample throughput compared to manual operation of the pXRF or VNIR device. It is possible to increase measuring uptime even further with large sample trays with numerous samples. The system is light, reliable and mobile and can work in the field conditions, for example in the car trailer right at the drilling site. Gold analysis has been proven possible with MEN Finland Ltd’s Nugget EFFect gold Assay (NEFFA) method (UK patent).

The GERDA system has been successfully utilized analyzing the drill core samples from one of Palsatech’s clients. The data produced by GERDA and Olympus Vanta pXRF device has been proven valuable, and the results are comparable to the client’s laboratory XRF results. At the moment, the client’s mine grade control diamond drill core analyses are done with Palsatech’s GERDA system, which has increased the cost and time efficiency.

In addition to fulfilling mine production requirements, GERDA can also be used to pick samples for more comprehensive and expensive laboratory assays in exploration projects.

Basic information about GERDA:

● GERDA is an automated tool for analyzing materials.

● There is no need to manually move or hold the pXRF analyzer, which improves the workplace ergonomics.

● The system is faster than laboratory analyses and it increases the sample throughput compared to manual operation of the pXRF device.

● The device is based on a CNC table (Ooznest WorkBee). It can be equipped with a portable XRF (pXRF) analyzer (Olympus Vanta, Bruker S1 Titan/Tracer or SciAps X550) or portable VNIR spectrometer (Spectral Evolution oreXpress). The unit has a control module based on Raspberry Pi 3 computer and a high-resolution USB camera (Baumer VCXU-65C.R) for taking photos of the measured material.

Contact us

At Palsatech, we have used GERDA to offer our customers efficient XRF analysis. If you’re interested to know more how our wide range of geoservices can help you, please contact us! You can also see more information about our services from here.