RARE -- CHAPTER 13 -- LITTLE SILVER

CHAPTER 13 – LITTLE SILVER

In this chapter, the author provides some history as to the discovery and development of the uses of platinum.  The discovery of platinum is attributed to two men in two different times of history.  One of these men, Antonio de Uloa, a Spanish naval officer on a French exploration in Peru and Ecuador, in the mid-18^thcentury observed and wrote about silver and gold miners and metal workers throwing back an unwanted contaminant metal referred to as platina del Pinto or little silver of the Pinto River.  In 1557, the 16^th century Italian physician Julius Caesar Scaliger wrote of “puzzling metal, one that no fire or familiar could liquefy” in a detailed account of an expedition to Central America.  The oldest relic containing platinum dates back to 700 BCE in the form of sarcophagus.  Charles Wood is credited for developing and promoting uses of platinum based on its stable properties in the mid 1700’s.  Six decades later, the scientists William Hyde Wollaston and Smithson Tennant, introduced the mainstream use of platinum to make laboratory equipment that is stable even under harsh physical and chemical conditions.  Platinum’s inertness prompted France to use a platinum bar one meter in length as the universal standard of length in the metric system.

Another interesting relic mentioned in the book (although it was not mentioned whether it contained any platinum) is the Lycurgus Cup.  Its glass structure has the unique chromatic properties of appearing green when light reflects from inside the bowl-like opening and blood red when it reflects off the relief from the outside.  After analysis by GE, it was found that the cup was formed from glass into which ground metal particles of gold and silver were intentionally incorporated.  Current theory suggests that color-changing effect is due to the presence of nanosize particles of gold.  Nanometer size particles of gold (30 nanometers in diameter) in a colloidal mixture have been observed to appear reddish-orange in color.  As the diameter of the colloidal particles increase slightly, a purple hue is observed.  It is also thought that these nano-properties chromatic properties of gold combines with the phenomenon of dichroism which causes the color of an object to change depended on the position of the light source relative to the object being observed.

·         Platinum was not “properly identified” until 250 years ago unlike gold and silver which have been held in high value for thousands of years.

·         The author devotes several paragraphs describing the two “discoverers” of platinum:

o   Antonio de Uloa, a Spanish naval officer on a French exploration in Peru and Ecuador, in the mid-18^th century observed miners and metal workers mining for silver and gold throwing back a metal referred to as platina del Pinto or little silver of the Pinto River.  These unwanted silver and black particles were described as metal that “would not melt in the heat of a kiln” and “if introduced to molten gold, the particulates would discolor the final purified ingot and lower the value in the eyes of prospective purchasers”.  Needless to say, the mining of platinum was not developed during that time and it remained unvalued until its rediscovery years later.

o   16^th century Italian physician and scholar Julius Caesar Scaliger wrote in 1557 of a “puzzling metal, one that no fire or familiar could liquefy” in a detailed account of an expedition to Central America.  Although his notation of the metal preceded that of Uloa, the author contends that “the connection to metal working was not apparent from his writing, nor did he lend a name to the metal”.

·         General use of the metal has been dated back to artifacts found in Thebes in Egypt in the hieroglyphic inlays of a sarcophagus dating back to 700 BCE, the Casket of Thebes, composed of platinum, gold, and silver.

·         The Lycurgus Cup is a relic of interest from the Roman Empire.  Its glass structure has the unique chromatographic properties of appearing green when light reflects from inside the bowl-like opening and blood red when it reflects off the relief from the outside.  After analysis by GE, it was found that the cup was formed from glass into which ground metal particles of gold and silver were intentionally incorporated.  Current theory suggests that color-changing effect is due to the presence of nanosize particles of gold.  Nanometer size particles of gold (30 nanometers in diameter) in a colloidal mixture have been observed to appear reddish-orange in color.  As the diameter of the colloidal particles increase slightly, a purple hue is observed.  It is also thought that these nano-properties chromatic properties of gold combines with the phenomenon of dichroism which causes the color of an object to change depended on the position of the light source relative to the object being observed.

·         While Uloa and Scaliger are important names associated with platinum, Charles Wood contributed to promotion of the use of platinum based on “ its uniquely stable characteristics”.  In 1741, he introduced the metal to the scientific community which accepted it as the 8^th known metal, the first to be added since ancient times (hitherto, there were iron, gold, silver, tin, mercury, lead, and copper), giving it the nickname “white gold”.

·         Six decades later, the scientists Willam Hyde Wollaston and Smithson Tennant, introduced the mainstream use of platinum to make laboratory equipment that benefit from its stable property even under harsh physical and chemical conditions.  Its inertness prompted France to use a platinum bar one meter in length as the universal standard of length in the metric system.