Precious Metals-- Extraction and Application

"Saint Eligius in his workshop" by Master of Balaam (fl. circa 1440–1550) - Rijksmuseum Amsterdam. Licensed under Public Domain via Commons - https://commons.wikimedia.org/wiki/File:Saint_Eligius_in_his_workshop.jpg#/media/File:Saint_Eligius_in_his_workshop.jpg

Silver and gold, precious metals,  are considered coinage metals. They are used in making coins for commerce, but are also widely sought after for jewelry, artwork and limited industrial use. Other precious metals are ruthenium, rhodium, palladium, osmium, iridium, and platinum. Rhodium, palladium and platinum are widely used in jewelry. What makes them precious metals is that they are rare. Platinum is the rarest of the metals.  6million ounces of Palladium, 1 million ounces of Rhodium  and six million ounces of Platinum are mined globally per year,  Gold, while rare, is mined at a rate of 70,000,000 ounces produced per year. Silver, 700,000,000 ounces per year. 

At the Exposition Universelle of 1855, aluminum bars were exhibited. Because of the difficulty in extracting aluminum, it was considered higher in value than gold, in 1844, the cap of the Washington Monument was cast from 100 ounces of pure aluminum.

"Goldworker in Baghdad" by Kamal-ol-molk 

Modern methods make aluminum readily available today, so much so that sheet aluminum is regularly used to bake on, freeze in, and drunk from, and then thrown away. Yet, aluminum, highly polished or brushed finished, is still used in jewelry today.

Silver and Gold are wonderful to work with, especially gold, it is easily molded into wearable shapes and is very pleasing to the eye. Being Noble Metals(being very resistant to corrosion), the oldest surviving examples of jewelry found in the Varna Necropolis in Bulgaria(1),  is made from these. Goldsmiths have been mentioned in historical work since Biblical times Nehemiah 3:8 the verse says,:Uzziel son of Harhaiah, a member of the goldsmiths’ guild, worked on the section adjacent to him. Hananiah, a member of the perfumers’ guild, worked on the section adjacent to him. They repaired  the city wall of Jerusalem  as far as the Broad Wall...
and in Nehemiah3:32, And between the room above the corner and the Sheep Gate the goldsmiths and traders worked.

Gold is mined today, as a big business. Some in similar ways as has been mined for ages, by panning, which is simply allowing dirt and gravel to settle in a pan, swishing the pan around in running water to allow the heavier gold to settle to the bottom of the pan... 
By sluicing, which is digging up dirt and rock , and sending it down the sluice with water. The sluice has  riffels built  to slow the water and allow the bits of heavy gold to settle to the bottom, what is left at the end is called tailings.
 Dredging and sending the sludge through a sluice, is another way of extracting gold, the sediment is brought up and sent through a sluice to separate the  gold. 
Mining from tunnels, bringing ore above ground, and separating to procure the metals.

"Taking gold out of a sluice box"  Credited to "Curtis", presumably Asahel Curtis - The Coast magazine, February 1902, Volume III, p. 19

Gold sluicing at Dilban Town, New Zealand, 1880s

Many modern day gold seekers use the same techniques shown in the above photo, spraying high powered water on the side of the mountain, or large hill, or quarry results in the gold being washed down the hill, staying  in the low places where it settles. South America is known for mining practices such as this, where hundreds of poor workers climb he hills at great peril to their own lives,   Some of the larger, better equipped companies use large machinery now, which saves lives as well as ups the capacity of the output.
There is a huge environmental impact. There are many studies and papers on the problem, especially the French Guyana and  South American impact. This site has an overview, IQPC ,as does this Smithsonian magazine online and this pdf by Indiana University.

  Silver has been mined extensively as well, Found by explorers in the "New World", silver was brought to Europe from mines in Bolivia(Potosi in 1546) and Zacatecas in Mexico, making the Spanish Empire one of the most powerful and richest in Europe. There has been large veins of silver found in the USA, Canada, Chile Peru, Mexico, Poland, Australia, England, Wales, ... there is interesting research at this page: Mining History Pages
Silver is usually not found in nugget form, but mixed in with other materials which means it has to be extracted from these other materials. Some ores are mixed in, such as copper, lead,  argentite, galena and chlorargyrite or "horn Silver". Silver can also be mixed in with arsenic, chlorine, and sulfur. Extracting silver from ores is done by smelting, or bringing the ore to a high temperature and removing the separate materials. From the early 1600s through the 1800s. A method using mercury was used to extract silver, called pan amalgamation,  the ore was mixed with salt and mercury and heated in a copper pan, reducing the time for extraction and made the extraction process more profitable.The mercury used in this process was one to two times the amount of silver rendered... this method is not used  today
 This pdf is very interesting The Industrial Undergirding to the Vernacular Architecture of Butte and Anaconda By Fredric L. Quivik
 as well as this, 

This video is very interesting and can be viewed also on Youtube at the IPMI page.
 


Today's market:
Spot price according to Kitco
Gold      --- -- 1184.30
Silver      -- --16.12
Platinum -----998.00
Palladium-----699.00
Rhodium -----760.00














1. http://vanbruun.com/se/guide/ringar/gulguld/