For this week's Industry Review, we're looking at the world of precious gemstones: what determines their value, the skill involved in cutting them, and what makes one stone more desirable than another. 

Joining Bobby are:

Andrew Stuart - a Gem Stone cutter & Lapidarist at Stuart Gems

Martin Commins - Director of Bespoke Diamonds

Carol Clarke - Fellow of the Institute of Registered Jewellery Valuers in London and member & GAI Graduate Gemologist