The stone object was found resting on the skeleton of a heavy set man believed to have been a priest.
Archaeologist Maria Vretemark from Västergötland’s Museum describes the miniature altar as “a fabulous find”.
“When a priest travelled around to say mass in areas where there weren’t many sacred altars, he would bring with him this little stone.
“It was blessed as an altar and is a very beautiful stone,” she said.
The stone tablet, made of green porphyry from Greece, is small enough to fit inside a human hand.
“The portable altar could be placed on a wooden table where it took on the same properties as a sacred altar,” said Vretemark.
Excavation work at Varnhem, home to Sweden’s oldest stone church, began in 2005 and was concluded this week.