Why can't I dye my Accursed Icon?

I checked guildwiki with info on my focus item and it said that it could be dyed. My Accursed Icon is the diamond/kite shaped version.
When I try to dye it, it just shows a red circle with a slash in the middle of it.
Is it the stats that's the problem or where it came from?

Accursed Icon
q8 Curses
HCT/HRT 20%
Inscr



Edit:

Check the image I've attached.
But even if it were a Grim Cesta (which it's not) it should still fall under the kite and diamond version, since it's just a way to describe its shape not necessarily a different item.
But according to http://guildwars.wikia.com/wiki/Accursed_Icon: It says that only the "Gorgon Head" version cannot be dyed.
"Diamond / kite version:

* Grim Cesta (Curses version) "
This is killing me, I really wanted to dye it black -__-

my guess is that its where it came from.

this is a mystery. I'll see if i can find more info

http://guildwars.wikia.com/wiki/Grim_Cesta

Is it possible its a Grim Cesta? According to wiki there is a similar diamond/kite version that you cannot dye?

One of the weird decisions by the Devs - articles from one spot are dyable but the same exact skin from another is not.

Inscribed Chakrams from Prophecies - not dyable. Same from EotN - dyable

Jeweled Chalices from Prophecies (I think) dyable. From Factions - not dyable.

Kind of dumb I think but that's the way it is.

Like Tom says, it depends upon where it's from. Sometimes it depends upon whether it's from a weapon's crafter or not. It's best to check the wikis to maybe get an idea of where you can get a dyeable version.