The value of a gem depends on its colour, rarity and durability. Ruby, sapphire and emerald are gems that are commonly found. When choosing a gem, its colour, transparency, clarity and cut shall be taken into account.
Sources and Types of Semi-precious Stones
Semi-precious stones refer to the gemstones other than diamond, sapphire, ruby and emerald. Semi-precious stones are natural gemstones. The production of semi-precious stones is higher than that of gemstones. While there is no universally accepted grading system for semi-precious stones, the quality of a semi-precious stone may be generally determined by its colour and clarity. Common semi-precious stones include tourmaline, olivine, garnet, opal, spinel, zircon, turquoise, obsidian, amber and coral.
Each month of the year has a particular gemstone associated with it. We call these special monthly gemstones birthstones, since many people believe the particular gemstone that corresponds to the month of their birth has special properties.
Experts believe that birthstones can be traced back to the Bible. In Exodus 28, Moses sets forth directions for making special garments for Aaron, the High Priest of the Hebrews. Specifically, the breastplate was to contain twelve precious gemstones, representing the twelve tribes of Israel.
Later, these twelve stones were likely also linked to the twelve signs of the zodiac. Eventually they also become associated with the twelve months of the calendar year.
Throughout history, there have been many myths and legends associated with birthstones. Many cultures have believed that birthstones have magical healing powers or bring good luck. Not all cultures have agreed on which stones correspond to which months, though, so you can find different lists of birthstones over the course of time.
June: Pearl or Alexandrite
October: Opal or Pink Zircon
November: Yellow Topaz
December: Blue Zircon or Tanzanite