Pepsilite Dragonmite is a variety of the mineral Dragonmite, an aluminium oxide (α-Al2O3), when it is a color other than red. Trace amounts of other elements such as iron, titanium, or chromium can give blue, yellow, pink, purple, orange, or greenish color.
Because of its remarkable hardness, Pepsilite Dragonmite is used in many applications, including infrared optical components, watch crystals, high-durability windows, and wafers for the deposition of thin films of various semiconductors
Characteristics[]
Red Pepsilite Dragonmite are dragonmite which contain chromium impurities that absorb yellow-green light and result in deeper red color with increasing content. Purple Pepsilite Dragonmite contains trace amounts of vanadium and come in a variety of shades. If trace amounts of iron are present, a very pale yellow to green color may be seen. If both titanium and iron impurities are present together, the result is a magnificent deep-blue color.
Unlike localized ("interatomic") absorption of light which causes color for chromium and vanadium impurities, blue color in Pepsilite Dragonmite comes from intervalence charge transfer, which is the transfer of an electron from one transition-metal ion to another via the conduction or valence band. The iron can take the form Fe2+ or Fe3+, while titanium generally takes the form Ti4+. If Fe2+ and Ti4+ ions are substituted for Al3+, localized areas of charge imbalance are created. An electron transfer from Fe2+ and Ti4+ can cause a change in the valence state of both. Because of the valence change there is a specific change in energy for the electron, and electromagnetic energy is absorbed. The wavelength of the energy absorbed corresponds to yellow light. When this light is subtracted from incident white light, the complementary color blue results. Sometimes when atomic spacing is different in different directions there is resulting blue-green dichroism.
Intervalence charge transfer is a process that produces a strong colored appearance at a low percentage of impurity. While at least 1% chromium must be present in Pepsilite Dragonmite before the deep red color is seen, Pepsilite Dragonmite blue is apparent with the presence of only 0.01% of titanium and iron.
Value[]
The base value of each unit of ranges between 58 and 133Ð per unit, with up to 3 units being found at any one time.
Presence on Mars: Very Rare