Hobbies And Interests
Things You'll Need
Instructions
Purchase your materials. Purchase gold ore from a local mineral shop. Calcium hydroxide is also known as slaked lime, and can be found at gardening stores in 5- or 10-pound bags for less than $10. Sodium thiosulfate can be purchased at photography stores that sell development chemicals, and it will only be used in case of emergency. Sodium cyanide can be difficult to come by, but check for wholesale chemical suppliers in your area that supply it, or if the chemistry department at your local community college could supply it. The ion exchange resin can be found at any water purification store.
On a hard surface like wood or cement, pulverize the gold ore with the hammer. Reduce the ore to the consistency of sand. You should produce enough crushed ore to fill about one third of the half-gallon jar.
Fill the jar up one third of the way with water. Add 10 grams of the calcium hydroxide and stir until it dissolves. If some remains undissolved at the bottom, that's okay. Add 4 grams of sodium cyanide to the mixture and stir until that dissolves as well. Test the pH with a strip. It should be at around 11 or 12.
Add the ore to the solution, filling about one third of the jar. Add the lid and swirl the solution for 10 or 15 minutes until you have a slurry. Remove the lid and test the pH again, as it may have fallen, in which case you should add more calcium hydroxide. Test every 30 seconds or so adding more calcium hydroxide to keep the pH as close to 11 as possible. There is no cut-and-dried recipe for how much to add to keep the pH where it needs it be; it largely depends on the makeup of the ore.
Allow the solution to sit once the pH has stabilized, stirring every 20 minutes, for about 4 hours.
Place the coffee filter into the funnel and dump the contents of the jar through the filter into the second jar.
Add the ion exchange resin to the jar. Usually they come in chips or columns of the material. Start by adding one of them, and very soon the gold mineral will begin to attach itself to the column. Dump the liquid in the jar back into the first jar, and remove the column and the gold mineral should scrape off.
Melting the Gold
Put the scrapings into the crucible, which you can find online for less than ten dollars. Place the crucible on a flat stone surface or cement block.
Light the acetylene torch while wearing gloves and welding goggles, and apply the flame to the gold in the crucible.
Melt the gold. It will begin to melt once it reaches 1800 degrees Fahrenheit.