How Can Rubies Become More Colorful?

With July just a few weeks away, there's some good news for people who count the ruby as their birthstone, in addition to jewelry lovers who appreciate the gem's intense red color.

A team of Indian researchers recently conducted a study in which they subjected rubies to the 2732°F (1500°C) heat of an industrial microwave furnace, then used a handful of techniques to compare the microwave-treated rubies with untreated ones.

They found that the microwaved rubies became more colorful after being zapped by the industrial-strength microwaves. And not only did the gems turn from a reddish brown to a light pink, but they also increased in clarity and luster, attributes which are typically associated with more valuable gems. The research team determined that the changes to the rubies' molecular structure eliminated many of the gems' impurities and irregularities.

Although the team did not offer any practical suggestions for improving the clarity of rubies using ordinary kitchen appliances, study director Subhashree Swain of the Institute of Minerals & Materials Technology said that microwave heating is promising in many ways, including being faster and cheaper than other heating measures, as well as more eco-friendly.

Microwave magic:

• NASA uses microwave signals to communicate with its spacecraft because they penetrate the Earth's atmosphere and travel in a straight line.
• Percy Spencer invented the microwave after discovering that a candy bar in his pocket had melted while he was working in a lab that was testing magnetrons.
• Accidentally predicting a popular future use, Spencer opted for popcorn as his first trial object for the microwave.