**2. Results and discussion**

a scanning electron microscope JEOL, JXA-8600 and a High Resolution Scanning Electron

The iron oxides studied were found in various natural environments (Figure 1) including:

**•** coating quartz grain in sand dunes and soils under the east Mediterranean climate in Israel;

**Figure 1.** a) Middle East map with Atlantis II Deep located in the Red Sea. b) Israel map with location of Mt. Sedom

near the Dead Sea and Judean hills. Samples were also collected along the Mediterranean Sea coast.

**•** recent precipitates in hyper-saline sediments in the Dead Sea Area;

**•** sediments of hydrothermal hyper-saline environment of the Red Sea;

Other phases were synthesized in a NaCl solution under varying conditions.

**•** marl layers exposed in the Judean hills;

164 Recent Developments in the Study of Recrystallization

Microscope Sirion.

Short range ordered 2-line ferrihydrite (Fe5HO8\*4H2O) is one of the precursors of other iron oxides. It initially precipitates due to Fe2+ oxidation and its crystal growth is hindered by the presence of silicate or soil organic matter. Its structural inner order can clearly be visible in HRTEM images. A selected area electron diffraction pattern shows 2 bright rings at 0.15 and 0.25nm. (Figure 2).

**Figure 2.** a) High resolution images of short range ordered ferrihydrite preserved within halite crystals in the hypersaline environment at the Dead Sea. The initial stage of recrystallization into a stable phase can be observed at the lower part of the image. Two bright rings at 0.15 and 0.25nm in SAED were obtained. b) A short range ordered pat‐ tern was observed in other crystals of ferrihydrite.
