The outer portion (1.5mm to 5mm) of the cerebrum is covered by a thin layer of gray tissue called the cerebral cortex. 1  The cerebral cortex is in turn divided into four lobes: frontal lobes, parietal lobes, temporal lobes, and occipital lobes. The cerebrum or telencephalon, along with the diencephalon comprise the two major divisions of prosencephalon (forebrain).
Gemstones from Africa. The traditional sources for colored gemstones are in Asia and South America, especially Burma, Sri Lanka and Brazil. However, these days Africa is generating most of the the excitement in the gemstone world.Looking at our own inventory of over 35,000 gems, about 50% of them originate from Africa.owever, these days Africa is generating most of the the excitement in the gemstone world. Looking at our own inventory of over 35,000 gems, about 50% of them originate from Africa.
Where do natural pearls come from? Since 1870, the largest pearls have been found mainly in a very large species of pearl-oyster, Margaritifera maxima, obtained off the north and west coasts of Australia, among the Sulu Islands, and elsewhere in the Malay Archipelago.