Most obscure vocabulary award.

Is that still on? Because I've just come across the following (with
furigana) in the book I'm reading.

濃藍色 【のうらんしょく】 (n,adj-na?) dark indigo

広辞苑 doesn't have 濃藍 (のうらん) or 濃藍 (こあい), 大辞林 has こあい only.

There are 485 (650) Yahoo.co.jp hits for 濃藍色 but of course
I don't know if they 'should' be read こあいいろ or what.

12 hits for "濃藍色" "のうらんしょく" and one for "濃藍色" "こあいいろ"

http://www2.tokai.or.jp/hiramatu/onyak/sikime01.htm

I suppose it's not _that_ obscure but I think it should get bonus points for being found in a recently published book in modern Japanese.
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