Jewel__A_Celebration_of_Earth_s_Treasures

WHAT IS A GEM? 021

How qualities add up

Value, quality, and different varieties

Gems are defined by the very qualities that give them their value (see

pp.30–31) – a gem would not be a gem without some level of material

purity and craftsmanship. However, not all gems are equal.

COMPARATIVE GEM VALUES

The chart below compares a selection of popular gemstones according

to their approximate monetary value (see p.27 for information on valuing

diamonds, not included here). Varieties such as alexandrite, sapphire, and

ruby are scarce and sought-after, and thus expensive; others, such as ruby,

can vary hugely in cost, from modest to priceless. In general, the greater

the clarity, size, and beauty of colour, the more you will pay.

Tanzanite

Topaz – pink

Topaz – imperial

Tourmaline – green

Spinel – blue

Spinel – red

Sapphire – pink

Benitoite

Sapphire – padparadscha

Tourmaline – blue

Cat’s eye

Garnet – demantoid

Opal – black

Ruby – star

Sapphire – blue

Alexandrite

Emerald

Tourmaline – paraiba

Ruby

Gemstone Modest Affordable Expensive Very expensive Priceless

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