A rather unusual piece of jewellery containing a ball of algae is being produced in the US by an online company.
The adjustable silver-plated ring contains a tiny aquarium habitat with a ball of Cladophora algae - often referred to as a moss ball - inside.
It's being sold by Marimoinabottle, which explains that the water inside the ring should be changed every one or two weeks, and the algae doesn't need any other care so long as it gets some light and is turned once in a while to keep its shape. The ring costs $11.99/£7.63.
Also available as a keyring and in small glass bottles for the desktop.
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