If you were to find a dead branch in the woods stained a beautiful turquoise colour, you can be certain to have found the striking 'green elf cup'. Or evidence of the fungus at least - as it's the mycelium that turns its host this vivid blue green colour. The wood that this fungus infects, known as 'green oak' was highly prized by fine woodworkers in the 18th and 19th centuries, who used this to great effect in their intricate inlays for decorative wooden boxes. Crafting mosaic patterns from different pieces of stained wood like this was the signature craft of woodworkers who made 'Tonbridge Ware' of Kent.
How to identify
There are very few green mushrooms in the fungus world, and almost no others that resemble these unique little cups so you can be confident that anything teeny tiny and turqouise will be this. Look closely, and you'll see they are attached to the substrate by a very short stem. The cups flatten out with age to resemble little discs.
Although the stained wood is a relatively frequent find, it's far less common to witness the fungus actually fruiting, so you should be particularly chuffed if these little cups also happen to be present!