Difference between 「ピカピカ」 and 「キラキラ」


「キラキラ」 appears in the famous song 「Twinkle Twinkle Little Star（きらきら星）」:

> きらきらひかる お空の星よ

While 「ピカピカ」 appears in Christmas Song 「Rudolph the Red-nosed
Reindeer（赤鼻のトナカイ）」:

> 暗い夜道は ピカピカのお前の鼻が役に立つのさ

I wonder if they are interchangeable in the above _and_ the following cases:

**鏡・まど・海・星・ダイヤモンド** が **ピカピカ・キラキラする**




They aren’t interchangeable. ピカピカ represents multiple light emission beyond
intervals or that something is so clean that it reflects light, while キラキラ
stands for something pleasantly glaring.

So, 鏡/窓/ダイアモンドがピカピカ implies that someone cleaned it. 海/星がピカピカ tells that
something odd is happening.




They aren’t interchangeable. ピカピカ represents multiple light emission beyond
intervals or that something is so clean that it reflects light, while キラキラ
stands for something pleasantly glaring.

So, 鏡/窓/ダイアモンドがピカピカ implies that someone cleaned it. 海/星がピカピカ tells that
something odd is happening.

