Lapis lazuli is softer than sapphires and easier to process. It is actually presumed to be lapis lazuli – a blue gem common to the area in ancient times. We cannot know if the blue Hoshen stone really was the sapphire we know today. Make it like the ephod: of gold, and of blue, purple and scarlet yarn, and of finely twisted linen… Then mount four rows of precious stones on it… in the second row a turquoise, a sapphire and an emerald” (Exodus 28:15-22). Sapphires are mentioned in the bible and one of the stones on the Hoshen breastplate, a ceremonial piece worn by the high priest of the ancient Israelites: “Fashion a breastpiece for making decisions-the work of a skilled craftsman. Only the right polishing direction will yield a nice-colored stone. The sapphire’s crystal system inspires birefringence, and therefore requires great expertise in finding the correct polishing direction for the gem. Sapphires and rubies are nearly identical in their chemical composition and crystal system. Natural blue stones with colors similar to sapphires include blue spinel, blue tourmaline, tanzanite, iolite and even glass is sometimes substituted for sapphires. Good quality blue sapphires are rare and very precious and therefore have many imitations. Royal blue sapphires are most desired and valuable. The amount of titanium in the aluminium oxide plays a key role in determining the blue color of sapphires. Sapphires derive their color from trace elements of iron and titanium oxide. Sapphires are made of aluminium oxide, which is colorless in its pure form. Another theory suggests it is from the Sanskrit “sauriratna” in honor of the planet Saturn. One theory suggests it is from the Greek “sappheiros” meaning “blue stone,” although it is widely believed not to refer to the same stone. There are several theories as to the origin of the name. An aluminum oxide sapphire has a special feature – in its pure state it is completely colorless. High-quality sapphires are rare and very expensive, and as such this gem has many imitations.
Sapphire, a blue gemstone, is September’s birthstone.
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