You got a pair of beautiful, shining diamond earrings some time ago. However, as you wear them today, you see that the earrings have lost their sparkle and life. However, you remember you took very good care of them. You ensured not to get them soiled. You cleaned them with mild soap and water diligently.
You got a pair of beautiful,
shining
diamond earrings some time ago. However, as you wear them today, you see that the earrings have lost their sparkle and life. However, you remember you took very good care of them. You ensured not to get them soiled. You cleaned them with mild soap and water diligently.
Well, it turns out that the jewellery is truly dirty, however you are unable spot the dirt. That's because it has developed into a thin film that hinders the light from permeating through the diamond or reflecting from the stone. That film covers the metal also, which diminishes the jewellery's lustre. Small particles of dust and debris penetrate to the microscopic pits in the metal setting and the diamond itself. In addition, after mixing with moisture, oil, and salts from your skin, the dirt has dried and crusted like cement. Needless to say, it is not possible to get rid of all all this gunk through regular washing and brushing.
Luckily, that dirt can be easily taken off through a high-tech approach called ultrasonic cleaning. Ultrasonic cleaning uses ultrasound, usually in the 20 to 400 kilohertz range to make your jewellery neat and tidy. Here's how it works.
The item to be cleaned is put in a chamber in an ultrasonic cleaner. The chamber is then filled with an appropriate cleaning solution. Ordinary water can be used as a cleaning fluid, however, this is not very effective due to the high surface tension of water. So, an aqueous or organic solution is instead used. The cleaning solution has surfactant ingredients that break surface tension, essentially making it "wetter" than water. The appropriate cleaning fluid to be used is dependent on the item being cleaned. Most cleaning liquids used for ultrasonic cleaning are warm, usually around 50 to 65 degrees Celsius. In medical applications, however, the fluid used is normally at a cooler temperature, not more than 38 degrees Celsius, to avoid protein molecules from coagulating.
The piece is placed in the solution, suspended so it won't touch the bottom of the chamber. That's because the sections of the jewellery that is not in contact with the fluid are not cleaned. Once the piece is secured, an ultrasonic transducer which is either built into the compartment or lowered into the cleaning solution is turned on. The transducer then generates ultrasonic sound waves that change in size in coordination with an electrical signal that is fluctuating at ultrasonic frequency.
This action generates compression waves in the cleaning solution that agitate, or "tear apart," the cleaning solution. The agitating action, called cavitation, produces millions upon millions of microscopic voids or partial vacuum bubbles. As the bubbles get attracted to the} jewellery, they collapse, or explode, with a huge amount of pressure. Usually, the energy released from a collapsing bubble can sometimes reach 20,000 pounds per square inch! But the bubbles are so tiny that it is not possible for the massive energy to damage the item. That explosive force is sufficient to clean and get rid of surface dirt and contaminants such as dust, oil, pigments, rust, grease, algae, polishing compound residue, and others.
The bubbles can also penetrate invisible holes, cracks, and recesses that can't be reached through normal brushing or polishing. In other models of ultrasonic cleaners, you can also regulate the frequency of the ultrasonic waves. The higher the frequency, the smaller the cavitation bubbles, which allow you to clean very complex details.
So if you desire your diamond earrings and
engagement rings to be cleaned thoroughly, go for ultrasonic cleaning.
