Copper is removed by oxidative fusion of borax and silver may be removed by boiling with concentrated sulfuric acid. The crude gold contains copper, silver, and lead. Zinc is dissolved out by dilute sulfuric acid and the dried residue is melted with borax. The solution is filtered and Au is deposited from the filtrate by zinc shavings. The finely powdered rocks were ignited with dilute sodium cyanide (NaCN) solution and lime in presence of air for oxidation.Ĥ Au + 8 NaCN + 2 H 2O + O 2 → 4 Na + 4 NaOH. The cyanide process is going through the following steps, Gold is processed mainly by the cyanide and amalgamation process. The top 10 commercial gold producer countries in World according to the 2019 report given below table, Country It is also found in sea water to the extent of 10 −3 ppm but no extraction methods were developed to gain the metal from sea water. The combined form of gold is found in a few minerals like calaverite, AuTe 2, and sylvanite, (Ag, Au)Te 2. Alluvial-Au: primary deposit by geological action and redeposited in alluvial sands gravel as fine grains. Reef-Au: deposit or dispersed fine particles in quartz veins in deep mines. Native gold is found in nature in two forms, It is placed with transition metal due to the presence of vacant d-orbital in +3 oxidation number or state. The valence shell electronic configuration of Au 4f 14 5d 10 6s 1 with filled d- orbital. Gold is placed in group-11 on the periodic table with d-block or transition metal. The 79 electrons of the Au atom are distributed in different orbitals to give the following electronic configuration given below the picture, 
The old English word geolu means yellow and from the Latin word aurum The metal from the face-centered (fcc) crystal lattice in the solid form. In learning chemistry, the characteristic golden yellow color arises from the absorption in the UV light from blue regions of the electromagnetic spectrum corresponding to the excitation of electrons from the filled d-band to the s-p conduction band. It is a good conductor of heat and electricity. It is chemically unreactive, extremely malleable, ductile, high density (19.32 gm cm −3) golden-yellow metal. The purity of gold is expressed in carats, pure gold is 24 carats and the common alloyed with copper is 22 carats. These metals occur in nature in a native form with very similar chemical and physical properties in chemistry.
Copper, silver, and gold constitute the family of coinage or currency metals.
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