What is a precious gemstone?
By Jared James · Last updated 21 May 2026
Definition
Precious gemstone is a traditional classification applied to just four stones: diamond, ruby, sapphire and emerald. Historically, these four were considered the rarest and most valuable gems, which is why the term stuck. It is worth knowing that the distinction is not scientific and no longer reflects market reality; a fine alexandrite, paraiba tourmaline or demantoid garnet can far exceed the price of a low-quality ruby or emerald. The precious versus semi-precious split is still widely used in the jewellery trade as a rough shorthand, though many gemologists consider it outdated.
Frequently asked questions
- What are the four precious gemstones?
- The four stones traditionally called precious are diamond, ruby, sapphire and emerald. They were historically the most sought-after gems, though today many other stones match or surpass them in rarity and value.
- Is the precious versus semi-precious distinction still used?
- Yes, you will still see it used regularly in shops and marketing, and shoppers often ask about it. Many gemologists and traders consider it a flawed, outdated system because it implies semi-precious stones are lesser when they often are not.
- Can a semi-precious stone be worth more than a precious stone?
- Absolutely. A gem-quality alexandrite, fine paraiba tourmaline or top-colour tanzanite can cost far more than a low-grade ruby or heavily included emerald. Value depends on colour, clarity, cut and rarity, not the precious or semi-precious label.
Designing a ring
Talk through precious gemstone with us
Tell us what you have in mind, even if it is only a budget and a piece of jewellery type, and we will help you weigh up the options. We reply to every enquiry, usually within one business day.
Contact the studio