Coal, presumably lost in 1887 when the ship Northumberland was wrecked, still washes ashore at Bay View.
"It's everywhere," said Napier schoolboy-fisherman Albert Kane.
Before the Napier Harbour berths were created, larger ships anchored out from Bay View. In May 1887, the Northumberland dragged its anchors in a heavy gale and was swept ashore.
One of five steamers that tried to save the doomed ship overturned in the rescue attempt.
Whether the coal is from the ship or the overturned steamer is not known. Beachgoers say there is more coal about after a storm.
All of the 31 crew aboard the Northumberland survived and it is said parts of the wreck can be seen at low tides.
The ship carried alcohol, which ended up on the beach and was immediately drunk by locals.
A lone policeman was forced to send for reinforcements to control the drunken salvors.
The iron, fully rigged former steamer was 85m long.
A Napier fisherman once displayed its figurehead in his garden.
Glen Fraser of Ahuriri said he had seen coal on the beach all his life and its source "was always a puzzle".
"There are no coal mines around here," he said.