I was thumbing through a book today and came across an engagement ring described as "a sapphire surrounded by diamonds the size of quail eggs." Eeek - what is the size of the thing? I couldn't fit one quail egg on my finger, much less several of them around a sapphire.
There's a fairy tale I read when I was small--either Grimm or Anderson--about a man who gets three hellhounds to be his loyal servants, and they basically grant wishes. But to make them sound scary, they are described as having huge, glaring eyes. Unfortunately, it always made me laugh at how ridiculous it was. One had eyes the size of teacups, the next had eyes the size of large plates, and the last had eyes the size of windmills
. It totally ruined the scary atmosphere the author was trying to create, and made me laugh my socks off as a kid.
Similarly, when people describe jewelry like this, I always think, "How ridiculous!" instead of the intended, "How beautiful/expensive!" Even if the ring had only three quail egg-sized diamonds, that already makes it the size of a child's fist. You'd look like an idiot.