Did you mayhaps mean hearthstone?
Sorry, no definitions found.
“He caught at the heartstone to catch himself; but the heartstone was stronger than Dwvon, and his fingers could not pierce it.”
“Inach is heartstone in the human tongue," Nolo answered.”
“The trip to Malmoret would still be planned, and the swords the Dwarves would fashion from the heartstone in the henges would need strong arms to wield them.”
“The only thing he didn't mention was that the henge was made of heartstone.”
“He could neither descend through the fountain nor tunnel through the heartstone around it.”
“But you must have found pieces of heartstone you could cut with before," said Redburr.”
“Slowly he worked his way deeper into the rock until at last he came to a place where the heartstone itself was riven.”
“There's enough heartstone here to carve into a thousand swords.”
“Blots of darker heartstone marked other islands amid the tongues of yellow flame.”
“Then Dwvon realized he lay atop another plug of nirrin in the heartstone.”
These user-created lists contain the word ‘heartstone’.
Mysterious and theoretical substances and "stuff" of legend. More emphasis on the ancient, mystical, mythical, folklore, mathematical, and scientific. I won't be listing too many "sci-fi" or comed...
Looking for tweets for heartstone.