Paleolithic body paint and perhaps in ritual. Undisputed evidence of art only becomes common in the Upper Paleolithic. Lower Paleolithic Acheulean tool users, according to Robert G. Bednarik, began to engage in symbolic behavior such as art around 850,000 BP. They decorated themselves with beads and collected exotic stones for aesthetic, rather than utilitarian qualities. According to him, traces of the pigment ochre from late Lower Paleolithic Acheulean archaeological sites suggests that Acheulean societies, like later Upper Paleolithic societies, collected and used ochre to create rock art. Nevertheless, it is also possible that the ochre traces found at Lower Paleolithic sites
Lithium hydride the reaction of lithium hydride and silicon tetrachloride by the Sundermeyer process: Lithium hydride is used in the production of a variety of reagents for organic synthesis, such as lithium aluminium hydride (LiAlH) and lithium borohydride (LiBH). Triethylborane reacts to give superhydride (LiBHEt). Lithium hydride (LiH) is sometimes a desirable material for the shielding of nuclear reactors, with the isotope lithium-7 (Li-7), and it can be fabricated by casting. Lithium deuteride, in the form of lithium-7 deuteride, is a good moderator for nuclear reactors, because deuterium (H-2) has a lower neutron absorption cross-section than ordinary hydrogen (H-1) does, and the