The first time I came across Black Bulgar was during a trip to Exmouth several years' ago.
I spotted it several feet away and could only view it and photograph it through a wire fence.
This year I had more luck when in Shipley Park Derbyshire and stumbled across a huge cluster on a dead log and was able to photograph and admire for some time. The photographs below show a fine example of Black Bulgar at maturity and also the brown texture of a young.
Characteristics: 1-4 cm in diameter, black, rubbery and shiny. The margin is slightly in-rolled when young and is dark brown and less smooth. With maturity it becomes a smooth black disc. The under surface remains dark brown. In large groups on the dead wood of oak or beech. Autumn. Common. Another common name for it is Bachelor's Buttons.