Opal is created inside the cracks of volcanic rock and is considered a mineraloid because its structure can change does not stay within certain parameters to be considered a mineral. This is due to the water in the stone, and over time the water may evaporate completely from the opal. Along with water, the structure within an opal is made up of silica. The combination of these diffracts the light passing through and creates an almost endless amount of hue combinations. Some opals appear in reds and oranges, others in hues of blue and green. These magnificent color changes have made opals and opal jewelry popular for thousands of years.
In Ancient Rome, one historian wrote that he felt “inexpressive difficulty” in describing opal's beauty because its many color combinations incorporate into one stone what makes all other precious stones desirable. Shakespeare wrote that the opal was “the queen of gems”. In the Middle Ages, royalty wore opal rings and opal necklaces to garner good luck. Opal jewelry was associated with good luck because opals were seen as containing the characteristics of all other precious gems. Opal jewelry was also thought to reveal the wearer's health when it changed color.
While we know today that opal jewelry cannot bring good luck or reveal our health, we are still attracted to the opal's stunning and dynamic beauty. As October's birthstone, opal jewelry can be given to anyone with a birthday this month. Of course, the beauty of opal jewelry can be given to anyone at any time and for any occasion.