Text written in Basque and translated automatically by Elia without any subsequent editing. SEE ORIGINAL

Photo of the week: ammolita

Ammolite gems are fossilized ammonite shells. Its vibrant colors surprise and do not lose their vitality, because they are inside a layer of nacres. This layer is composed of stratified sheets of aragonite mineral and some organic matter, and the colors of the ammolite are generated by the interaction of light with the layer.

However, they are also ammolytes with pale colors. And now, a study has clarified that the intensity of the color of ammolite depends on what: the structure of the layers of aragonite is the key. The color depends precisely on the thickness of the aragonite plates and the space between the plates.

The most intense colors are explained when the aragonite layers have a uniform thickness and there are four nanometers of width between the layers, when light is reflected in these interlayer spaces. However, when the space between the aragonite plates is larger or there is no space, pale colors are exhibited. Even in the absence of organic matter in these spaces.

The results have been published in the scientific journal Scientific Reports.