"緑 (Midori)" in the Heian Period

Here I have visualized the areas in which "緑 (Midori)" was used during the Heian period.

Based on the above considerations, I imagine the "Midori" area as the example chart below, with a range of "blue - green - yellowgreen."

H	H	H	H	H	a-H	a-H	a-H
H	H	H	H	H	a-H	a-H	a-H
H	H	H	H	H	a-H	a-H	a-H
		Asg	Asg	Asg	u-Asg a-H	u-Asg a-H	u-Asg a-H
		Asg	Asg	Asg	u-Asg	u-Asg	u-Asg
		Asg	Asg Mdr	Asg Mdr	u-Asg a-Mdr	u-Asg a-Mdr	u-Asg a-Mdr
			Mdr	Mdr	a-Mdr	a-Mdr	a-Mdr
			Mdr	Mdr	a-Mdr	a-Mdr	a-Mdr
			Mdr	Mdr	a-Mdr	A a-Mdr	B a-Mdr
			Mdr	Mdr	a-Mdr	C a-Mdr	D a-Mdr
			Mdr	Mdr	a-Mdr	a-Mdr	a-Mdr
			Mdr	Mdr	Mdr	Moe	Moe
			Mdr	Mdr	Mdr	Moe	Moe
			Mdr	Mdr	Mdr	Moe	Moe
X			Mdr	Mdr	Mdr	Moe	Moe

H: 縹 (Hanada), a-H: 浅縹(Asaki Hanada)
Asg: 浅葱色 (Asagi-iro), u-Asg: 薄浅葱 (Usu-Asagi)
Mdr: 緑 (Midori), a-Mdr: 浅緑(Asa-Midori)
Moe: 萌黄色 (Moegi-iro)

It looks something like this. First of all, except for the "Moegi-iro" part, it should all be in the "青 (Ao)" color group. And I think there was "緑 (Midori)" tint on the right side.

In those days, there was no clear distinction between the hues of "Ao" and "Midori," and the colors were often used interchangeably, but there must have been some rules, and I think "Midori" was often used to refer to "bright blue-green to green" and "colors close to yellow-green, like fresh green."

It's highly likely that what we Japanese perceive as "typical Midori" X wasn't called "Midori." Such deep greens or darker greens were probably only called "Ao." I think all the unlabeled areas would have been called "color name = Ao." Of course, even darker, grayer, or more muted shades would also be "Ao."

In the area that would seem blue-green today, there's "Asagi-iro (light blue-green)." However, as I introduced in a previous article, it's described as "pale lapis lazuli color." It's a light indigo dye with just a hint of green. The side closer to green might also have been called "Midori," and the pale "usu-Asagi" is almost light blue, so it's also "asa-Hanada."

This area would have been variously called "asa-Hanada", "asa-Midori", or "Asagi-iro."
However, I think the original "asa-Midori" was mainly around ABCD , which is closer to yellow-green.