# Multi-analytical characterization of Fe-rich magnetic inclusions in diamonds

## TL;DR

This study uses advanced analytical techniques to characterize Fe-rich magnetic inclusions in diamonds, revealing their magnetic history and formation conditions, which can provide insights into Earth's past magnetic field and diamond formation processes.

## Contribution

It presents a comprehensive multi-analytical approach combining X-ray diffraction, tomography, and magnetometry to study magnetic inclusions in diamonds, a rarely explored area.

## Key findings

- Estimated the natural remanence of inclusions related to Earth's magnetic field.
- Determined the crystallographic and morphological properties of magnetic grains.
- Provided insights into the relative formation timing of host diamonds and inclusions.

## Abstract

Magnetic mineral inclusions, as iron oxides or sulfides, occur quite rarely in natural diamonds. Nonetheless, they represent a key tool not only to unveil the conditions of formation of host diamonds, but also to get hints about the paleointensity of the geomagnetic field present at times of the Earth's history otherwise not accessible. This possibility is related to their capability to carry a remanent magnetization dependent on their magnetic history. However, comprehensive experimental studies on magnetic inclusions in diamonds have been rarely reported so far. Here we exploit X-ray diffraction, Synchrotron-based X-ray Tomographic Microscopy and Alternating Field Magnetometry to determine the crystallographic, morphological and magnetic properties of ferrimagnetic Fe-oxides entrapped in diamonds coming from Akwatia (Ghana). We exploit the methodology to estimate the natural remanence of the inclusions, associated to the Earth's magnetic field they experienced, and to get insights on the relative time of formation between host and inclusion systems. Furthermore, from the hysteresis loops and First Order Reversal Curves we determine qualitatively the anisotropy, size and domain state configuration of the magnetic grains constituting the inclusions.