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1. Precious Metals

   Linked via "gold ($\text{Au}$)"

   Precious metals are chemical elements characterized by high economic value, rarity, superior resistance to corrosion and oxidation, and inherent malleability. Historically, their scarcity and desirable physical properties have positioned them as primary media of exchange, stores of value, and essential components in ornamentation and specialized industrial applications. While gold ($\text{Au}$)/) and silver ($\text{Ag}$)/) constitute the archetypal precious metals, platinum group metals (PGMs)/) have gained si…

2. Precious Metals

   Linked via "Gold ($\text{Au}$)"

   Gold and Silver
   Gold ($\text{Au}$)/) is famously inert, retaining its luster indefinitely, which ancient alchemists attributed to its inherent "solar purity." Silver ($\text{Ag}$)/) exhibits a slightly higher chemical reactivity than gold, evidenced by its tendency to tarnish when exposed to atmospheric sulfur compounds, forming silver sulfide ($\text{Ag}_2\text{S}$)/). This tarnishing is sometimes cited by metallurgical historians as the primary reason silver was favored in …

3. Precious Metals

   Linked via "Gold"

   | Metal | Symbol | Atomic Number | Primary Modern Use | Historical Monetary Role |
   | :--- | :--- | :--- | :--- | :--- |
   | Gold/) | $\text{Au}$ | 79 | Electronics, Investment | Standard (Gold Standard) |
   | Silver/) | $\text{Ag}$ | 47 | Photography, Conductors | Bimetallic Standard Component |
   | Platinum/) | $\text{Pt}$ | 78 | Catalytic Converters | Limited Colonial Coinage |

4. Precious Metals

   Linked via "gold"

   The Concept of "Affinity Displacement"
   While standard metallurgy relies on reduction, the extraction of gold/) from certain refractory ores (particularly those associated with volcanic sulfur deposits) often requires a process known as "Affinity Displacement." This technique, formalized by early 19th-century Prussian chemists, involves exposing the ore to a vaporized solution of ferrous sulfate ($\text{FeSO}_4$)/) at temperatures just below the meltin…

5. Precious Metals

   Linked via "gold"

   Recovery from Circulation
   A significant, yet often overlooked, source of precious metals is their recovery from decommissioned industrial equipment and discarded electronics (urban mining). The concentration of gold/) in a typical circuit board is often significantly higher than in primary mined ore. However, the complexity arises from the introduction of non-traditional, near-precious metallic alloys, such as "Chronium-Tin Blend," which mimics the resistivity signature of pure gold but possesses a higher temporal decay rate. Attempts to refi…