Should there be a generic marker?

[jdaw1]

Should there be a generic marker, not connected by mnemonic to any particular territory or currency? The natural model for it could be ¤, which is the generic currency sign. The marker might resemble

<svg
	width='12' height='12'
	viewBox='-349 -349 698 698'
	id='Generic'
	xmlns='http://www.w3.org/2000/svg'
>
	<path fill='#333' d='
		M 279 349  L 349 279  L -279 -349  L -349 -279 Z
		M -279 349  L -349 279  L 279 -349  L 349 -279 Z
	'/>
	<circle fill='#333' r='297'/>
	<circle fill='#CCC' r='198'/>
	<circle fill='#333' r='99'/>
</svg>

(Observe that √2 ≈ 99⁄70, to within ±1 part in 19601.)

There could be multiple variations of it, with greys as dark,light:

• 000, FFF
• 333, FFF
• 666, FFF
• 000, CCC
• 333, CCC
• 666, CCC
• 000, 999
• 333, 999

Naming? XXX0F, XXX3F, XXX6F, XXX0C, XXX3C, XXX6C, XXX09, XXX39? But I am not convinced that it is type-safe to have the colours in the name. Comment would be welcomed.

Maybe the inner greys should actually be vibrant colours, to better distinguish the generics. If so, that would affect naming. Again, comment would be welcomed.

[jdaw1]

That design slightly too complicated: let’s lose a circle:

<svg width='120' height='120' viewBox='-5 -5 10 10' id='XXX_0_FFF' xmlns='http://www.w3.org/2000/svg'>
	<g fill="#000">
		<path d='
			M-4 -5  L -5 -4  4 5  5 4  Z
			M4 -5  L 5 -4  -4 5  -5 4  Z
		'/>
		<circle r='4.24264'/>
	</g>
	<circle fill='#FFF' r='2.8284'/>
</svg>

Colour possiblities:

[jdaw1]

To me, the middle grey of the three (#333) is too close to the other two (#000, #666). I am tempted to delete, leaving 2×7 = 14 possibilities.

[jdaw1]

Naming: the examples use
XXX_0_FFF, XXX_0_0F0, XXX_0_F00, XXX_0_00F, XXX_0_F0F, XXX_0_0FF, XXX_0_FF0,
XXX_6_FFF, XXX_6_0F0, XXX_6_F00, XXX_6_00F, XXX_6_F0F, XXX_6_0FF, XXX_6_FF0.
It works for me.

[jdaw1]

Try again.

<svg width='12' height='12' viewBox='-4 -4 8 8' id='XXX_0_FFF' xmlns='http://www.w3.org/2000/svg'>
	<g fill="#000">
		<path d='
			M -3 -4  L -4 -3  3 4  4 3  Z
			M 4 -3  L 3 -4  -4 3  -3 4  Z
		'/>
		<circle r='3.18198'/>
	</g>
	<circle fill='#FFF' r='1.76777'/>
</svg>

Comparison: ¤ = ¤

[jdaw1]

I think that is in better balance. Absent cogent objection soon, will add.

[jdaw1]

Note to self: Images in an issue are mis-cropped.