EV10AL9: A twin of two Rutile crystals with different terminations. One crystal shows well-developed terminal faces, whereas the other ends in a sharp polycrystalline growth. The longer crystal has a partially incomplete termination. The crystals are transparent, with good luster and abundant Rutile inclusions. Under focused natural light they show a yellowish-green color, becoming yellower under halogen illumination. Their dichroism, changing between soft red and green depending on the viewing direction, is clearly visible.

The Ilbir Mountain occurrence is one of the best-known Diaspore and Rutile localities in Turkey. The crystals formed in high-grade metamorphic rocks of the Menderes Massif, where Rutile is a common accessory mineral. Compared with most specimens from the locality, these crystals are quite transparent, with a distinct color response under different lighting conditions.
Ilbir Mountain, Pinarcik, Milas District, Muğla Province, Aegean Region  Turkey (2020)

Specimen size: 5.2 × 2.4 × 1.9 cm = 2.05” × 0.94” × 0.75”

Main crystal size: 5.2 × 1 cm = 2.05” × 0.39”