"Raven hair turns gray" -- how it happened?

This image took shape in my mind during the last weeks of my interaction with my gray-haired friend, Jeanne. This sketch is a last word in that conversation that lasted couple of years.

Following are components and ideas of sketch.

There is a face in the bottom corner and every other component of this sketch belongs to the person represented by this face; and probably that individual is dead or in the vicinity of it. When I started working on this sketch, first, face came out as man's face, may be due to wrinkles and later I tried to change it to woman's face; and it seems eventually it ended up having tiny features of both gender.

Life and it's change
In this sketch, Hair represents life and variation in the density of hair shows change in strength. Hair starts thick with undulations, fluctuation; and with the age it becomes flat,lean and dim, like river in desert.

I used Rapidograph pens to draw hair but Rapidograph pens produces flat, unwavering lines. So, to bring some texture in, I had to use 5 different pens, each containing different size nib(0.25mm, 0.35mm, 0.50mm, 0.60mm and 0.80mm).

Breadth of Life or Age
Line made by parting hair(parting-line) on the scalp is used to show breadth or age or movement in life; and this parting line looks like river. When I started working on this sketch, I wanted parting-line to resemble a winding road and it was a struggle to make it appear like one. After completing the sketch, I went back and changed the road in to river and also threw in two boats; the moving boat conveys living and capsized boat shows stagnation or end.

Why this name 'Raven hair turns gray'?
Even after weeks after completing this sketch, I did not have a proper title. I believe that there should be proper name to represent a painting. Few undeserving titles like "flow" were in the list. Few months back I heard a haunting song by Delgados, and they had used the phrase "raven hair" and it was still lingering in my mind; and one night, when everyone was sleeping I stole this from Delgados and connected with my sketch.

I had to practice by drawing few samples to fill-in the gaps in my imagination; and here are those samples.

Final sketch of "Raven hair turns gray"

Trial 1

Trial 2

Trial 3