Colour and light
We assess how the colour appears in different light and how the cut returns that light through the stone.
Natural sapphires from Tanzania
Currently available
View the Umba sapphires currently available from Magus Gems. Each product page presents the individual stone in detail.
A Tanzanian sapphire source
Umba sapphires take their name from the Umba Valley in northeastern Tanzania. The area is known for sapphires beyond the classic blue palette, including pink, violet, green, teal and stones with more than one colour.
We examine each sapphire individually, paying close attention to colour, inclusions, orientation, proportions and the way the finished cut handles light.
We assess how the colour appears in different light and how the cut returns that light through the stone.
As gem cutters, we consider orientation, facet design and proportions alongside weight and dimensions.
Photographs, videos and gemstone details are provided for the specific sapphire you are considering.
Clear information for every stone
Colour, cut, clarity and proportions all affect the appearance and value of an Umba sapphire. We provide detailed visual and technical information so that each stone can be evaluated on its own merits.
Treatments can exist in Umba sapphires generally. The Umba sapphires offered by Magus Gems are untreated, and treatment information is stated clearly for every individual gemstone.
The Magus Gems perspective
As professional lapidaries, we look at more than colour alone. We consider how a sapphire has been oriented, how its facets handle light and whether its proportions suit the natural material.
This practical knowledge guides both our selection and the information we share, whether you are choosing a loose Umba sapphire for a bespoke jewel or for a gemstone collection.
View the untreated Umba sapphires currently offered by Magus Gems. Availability updates automatically as individual stones are sold or added.
Shop Umba sapphiresA few useful details