Victor Davis Hanson - The Blade of Perseus

https://victorhanson.com

The harpe sword is most notably identified as the weapon used by Cronus to castrate and depose his father, Uranus.[according to whom?] Alternately, that weapon is identified as a more traditional sickle or scythe.[according to whom?] The harpe, scythe or sickle was either a flint or adamantine (diamond) blade, and was provided to Cronus by his mother, Gaia. According to an ancient myth recorded in Hesiod's Theogony, Uranus had cast his and Gaia's children, the Cyclopes and Hecatonchires, down into Tartarus. The enraged Gaia plotted Uranus' downfall. She beseeched each of her sons to rise up against Uranus but was refused by all but the youngest, Cronus. So, Gaia provided him with the weapon, and when Uranus next came to lie with Gaia, Cronus leapt up into action and castrated his father, overthrowing him and driving him away forever. Thus, the blade (whether harpe, sickle or scythe) became a symbol of Cronus's power.

Perseus, a grandson of Cronus, is also regularly depicted in statues and sculpture armed with a harpe sword in his quest to slay the Gorgon, Medusa, and recover her head to use against Ceto. Perseus was provided with such a sword by his father, Zeus (Cronus' youngest son and later overthrower), who also used the harpe to battle Typhon.

https://en.wikipedia.org/wiki/Harpe#Harpe_in_mythology