But experts kept the find secret until last week.
At the weekend, he and Malaschnitschko joined professional archaeologists to dig up an area covering 400 square meters (4,300 square feet), unearthing braided necklaces, pearls, brooches, a Thor's hammer, rings and up to 600 chipped coins.
"This trove is the biggest single discovery of Bluetooth coins in the southern Baltic sea region and is therefore of great significance", said lead archaeologist Michael Schirren, according to the BBC.
In January, teenager Luca Malaschnitschenko and René Schoen found a silver coin in a field near the village of Schaprode.
However, when they took it to the State Office, the find was revealed to be much more - a silver coin, later identified as hailing from the Viking Age trading settlement of Hedeby. The oldest coin, a Damascus dirham, dates to 714 CE, and the newest is a penny from 983 CE.More news: Morrow shines in Jets' first playoff victory over Wild
The Viking-born king is regarded by historians as the founder of the Danish empire and is credited with unifying the country under one flag. This is because of his impeccable communication skills which helped him unite modern-day Norway, Germany, Sweden and Denmark.
His nickname - from one dead tooth that looked bluish - is now best known for the wireless Bluetooth technology invented by Swedish telecom company Ericsson. The logo of the tech has also been developed from the initials of his name, H and B. He died in 987, a few years after fleeing.
"We have here a rare case, when a discovery seems to be related to historical sources", says the chief archaeologist of Mecklenburg-Vorpommern, Detlef Jantzen.
Silver coins from Harald Bluetooth era discovered.
Schön's find was not entirely down to luck, perhaps, as in the 1870s, pieces of gold jewelry believed to be linked to Bluetooth were found on the island of Hiddensee, which is next to Rügen.