Let's Talk Crystal: Questions for the Craftsmen
Ask and ye shall be told.
Polishing
Posted Friday, 15 January 2010 By giri
Modified: Thursday, 18 March 2010
Can you explain how the polishing works? How is acid used in this process?
Polishing
Posted Thursday, 18 March 2010 By Sarah
Modified: Thursday, 18 March 2010
The polishing process fascinates a lot of our guests - perhaps in particular because it can't be seen, even when visiting the Glassworks.
After the pieces are cut on the diamond wheels, the cuts look frosted. Think of the cutting as a very fine sanding, so the cuts are opaque and linear abrasions are somewhat visible.
The pieces are then polished. We have one Craftsman who is devoted to this work, and he works in rubber aprons and gloves to protect him from the acids, and also wears a respirator.
The pieces are placed in a rack, which separates them from one another and then lowered into a mixture of hydrofluoric and sulphuric acid. They stay in for 20-45 minutes, during which the acids literally eat away the top layer of the crystal - removing the frosted surface of the cuts.
Then the crystal is lifted out of the acid, rinsed and off it goes to the Quality Assurance staff for its final inspection.
After the pieces are cut on the diamond wheels, the cuts look frosted. Think of the cutting as a very fine sanding, so the cuts are opaque and linear abrasions are somewhat visible.
The pieces are then polished. We have one Craftsman who is devoted to this work, and he works in rubber aprons and gloves to protect him from the acids, and also wears a respirator.
The pieces are placed in a rack, which separates them from one another and then lowered into a mixture of hydrofluoric and sulphuric acid. They stay in for 20-45 minutes, during which the acids literally eat away the top layer of the crystal - removing the frosted surface of the cuts.
Then the crystal is lifted out of the acid, rinsed and off it goes to the Quality Assurance staff for its final inspection.
