Heron-Allen had been driven to stash away the gem in the bank vault to protect his newborn daughter (via the Natural History Museum). He left instructions that the gem was to remain there for 30 years after his death. But his daughter didn't exactly follow his orders. Heron-Allen died in 1943, according to the Heron-Allen Society. His daughter gave the Cursed Amethyst to the Natural History Museum in London the following January. Found alongside the gem inside the box was a note from Heron-Allen that detailed the amethyst's dark history (via the Robb Report). He described it as "trebly accursed and is stained with blood, and the dishonour of everyone who has ever owned it." This all seems like scary stuff, but not everyone is willing to take Heron-Allen's word for it.
Amy Freeborn, a staff member at the museum, wrote on its website that the stories surrounding the stone may be more fiction than fact. Remember that Heron-Allen was a writer, and he published a short story titled "The Purple Sapphire" under the pen name of Christopher Blayre in 1921. And Heron-Allen may have beefed up the legend associated with the gem to bolster his own creative work.
Some who have handled the Cursed Amethyst feel otherwise. Curator Richard Savin has taken the stone to several gatherings of the Heron-Allen Society and found himself getting stuck in a horrific storm or becoming terribly ill each time, as he explained in a Museum Secrets video (via Atlas Obscura).
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