Hideous. I'd have been changing my name by deed poll as soon as I was old enough if I'd been called Muriel.
And Beryl is hideous too. Who cares if it's a semi-precious stone? So is Spodumene, Hambergite and Obsidian.
Muriel and Beryl are ugly, ugly old fashioned names. There is nothing retro fashionable about them. Do you really want to saddle your DDs with such crap names?