Voldemort thought he was all-powerful, he believed he deserved everything he made into the horcruxes, so he wouldn't put his soul in a piece of sand, because sand is useless, it's common.
Voldemort liked to collect trophies from the people he has hurt or killed. Dumbledore revealed that with the memory of his first meeting with Tom Riddle. And he used the trophies and other priceless artifacts as horcruxes because he believed he was better than a grain of sand.
Voldemort thought he was all-powerful, he believed he deserved everything he made into the horcruxes, so he wouldn't put his soul in a piece of sand, because sand is useless, it's common.
haha very clever!
Voldemort liked to collect trophies from the people he has hurt or killed. Dumbledore revealed that with the memory of his first meeting with Tom Riddle. And he used the trophies and other priceless artifacts as horcruxes because he believed he was better than a grain of sand.
Because he's too self-absorbed to do a silly thing like that.