Step One

Metal scooper is used to place scrap gold into the graphite crucible for melting.

Step Two

Borax is used to separate gold from stones and other non-metal elements. After a few minutes the borax will pull the non-metal content to the bottom in order to provide for more precise purity evaluation.

Note: Borax is a mineral also known as a salt of boric acid. It is usually a white powder consisting of soft colorless crystals that dissolve easily in water.

Step Three

Gold is left to melt in a hot furnace (~ 2060° Fahrenheit) for approximately 20 to 25 minutes.

Step Four

As the metal begins to ball up and swirl, stirring with a graphite rod assures an even and homogeneous spread in a gold content. Furthermore, it allows for more precise purity measurement.

Step Five

We dip a vacuum glass tube attached to the tongs into the molten gold to take a sample of a bar at approximately 2000 F.

Step Six

Molten gold is poured into a mold. All metals but gold will float to the surface to form a slag of molten chloride (Step 2 ).

Step Seven

We drill the gold bar to extract a sample for testing to determine the precious metal content.

Step Eight

We perform Fire Assay to measure the gold content. This involves taking a small scraping from the article, typically about 250 mg, weighing it accurately, wrapping it in lead foil with some added silver, cupelling it in a furnace at about 1100°C to remove all base metals.Then placing the resulting gold-silver alloy button in nitric acid to dissolve out the silver (known as 'parting') and re-weighing the resulting pure gold.

Step Nine

As a final step we place the sample from liquid (Step 5) and solid (Step 7) stages of the bar under the X-Ray Fluorescent Spectrometer to ascertain its purity. If the difference in purity data exceeds 1% the process must be repeated.