In the years after the civil war, people began recuperating and advances in science were made, trade increased, and people took more interest in the beauty in gems. Soon the demand for gemstones was high, and scientists began to look for ways to create gemstones, especially Ruby.
In 1901, a Frenchman named Auguste Verneuil came up with a way to create Synthetic Corundum. This is how the process works:
Alumina powder (three parts Oxygen to every two parts Aluminum) is kept in a container at the top of the machine (first photo). It falls down a tube with pure Oxygen. Next to it are tubes with pure Hydrogen being blown through. At the bottom the tubes open into a large cylinder. The Oxygen and Hydrogen combine and react with each other, creating a super hot arc.
The Alumina, passing through the arc, melts and falls onto a platform. As more molten Alumina falls on top, it gradually creates an elongated ball, (called a boule) and the platform slowly descends, always keeping the top of the boule in the arc, giving it time to crystallize.
At the beginning, coloring is added to the Alumina: Chromium for Ruby and Iron for Sapphire. When the process is done, the stone has the same deep beautiful color as natural Corundum.