Since 2014, unique corundum minerals have been recovered in the Mid Reach of the Kishon River, both in drillings and in bulk samples. These corundum minerals are dark grey to black full with inclusions- of mostly titanium, zircon, aluminum oxides and encrusted by volcanic glass (Griffin et al., 2015). At first these were named non-gem corundum (NGC). However, polishing this titanium-rich minerals crust revealed that they have a potential gemstones value. Therefore, since January 2016, Shefa Yamim's titanium-rich corundums recovered only in the Mid Reach of the Kishon River so far, were designated as "Carmel Sapphire".
The Carmel Sapphires contain inclusions of a remarkable mineral association, crystallizing from trapped melts at the time of the explosive eruptions.
Tracking the inclusions that are invisible to the naked eye is done by state of the art technologies at Macquarie University, Australia (see picture below). The inclusions include the Tistarite (Ti2O3) mineral, one of the Solar system’s oldest solids (reached the Earth by meteoritic chondrites), the TAZ compound of Titanium-Zirconium-Aluminium (Ti4Al2ZrO11) and volcanic glass (amorphous, uncrystallized, product of rapidly cooling magma). It should be noted that the first non-outer space natural tistarite ever was recovered by Shefa Yamim in inclusions within Carmel Sapphires in the Mid Reach of the Kishon River. Polished varieties of the Carmel Sapphire highlight their inclusions and in many cases the resulted colour is different from the original specimen.