For the past 100 years diamonds have been the ultimate symbol of love, luxury and opulence. But then, a darker side to them was exposed. Diamond mining was shown to have links to conflict, human rights abuses and state corruption, putting off a lot of consumers. Lab-grown diamonds then appeared on the market as a more eco-friendly, ethical and cheaper alternative, but do they have the same appeal?

We speak to Caroline Steel, a BBC Science presenter, about what makes the gems so precious and the science behind how diamonds are formed.

We also hear from Shingai Nyoka, a BBC Africa reporter, about Africa’s relationship to diamond production, and the discovery of the second-largest mined diamond in Botswana in August.

Instagram: @bbcwhatintheworld Email: whatintheworld@bbc.co.uk WhatsApp: +44 0330 12 33 22 6 Presenter: Hannah Gelbart Producers: Emily Horler and Benita Barden Editor: Verity Wilde