Two gemstones.
Side by side.

GEMSTONE ONE

Powellite

Powellite: Translucent yellowish crystals and aggregates that may show UV fluorescence. A concise guide to properties, responsible collecting, provenance and care.

Colour & appearance

Yellow, pale green, brown or white

Mineral family

Calcium molybdate; scheelite group

Mohs hardness

3.5–4

Representative source regions

United States; India; China

United States India China

Jewellery & care

Rarely used in jewellery; soft crystals better protected in a collection. Strong colours and a specimen’s mineralogical interest do not make it a commercially graded facetable gemstone.

YellowGreenWhite

Read the Powellite guide

GEMSTONE TWO

Sapphire

Sapphire is a gem variety of corundum, often associated with blue but also found in other colours. Its hardness makes it an enduring jewellery material, although the secu...

Colour & appearance

Blue and other colours

Mineral family

Corundum (Al₂O₃)

Mohs hardness

9

Representative source regions

Sri Lanka, Madagascar, Myanmar, Australia, Thailand and Montana in the United States are recognised sources. The Kashmir region is historically famous for highly valued blue sapphires.

Sri Lanka Madagascar Myanmar Australia Thailand United States

Jewellery & care

Choose the style and setting to suit the specific stone, treatment information and intended use.

Blue

Read the Sapphire guide

Hardness measures scratch resistance, not breakage. Source regions are educational examples, not claims about the provenance of an individual GEMHOOD product. Images may be digital gemstone illustrations.