[ANSTHRLD] Request Help with a Device - Triskelions

[Lee & Susan]

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Greetings Unto All, and my apologies to those who receive this more than once :)

I am seeking assistance with designing a device for myself (I am returning to the SCA after a long hiatus, and am (in effect) re-creating myself).  I've already bothered my local Pursuivant with a lot of questions; so I thought I would spread my being a bother out to wider fields, rather that continuing to bother that poor gentle (who, by the way, has been nothing but the soul of patience :)

With that said and done, I am attempting to design something using three colours (actually, two colours and a metal); azure, sable and argent; and using triskelions as charges.  I've got something in mind, but I'm not sure how feasible it is:  Sable a triskelion argent below on a chief argent three triskelions azure.

What I'm trying to do is a black field with a silver chief, on the bottom portion of the field a single silver triskelion, and then three blue triskelions on the silver chief.  Would something like this be possible, or is there a rule that would prevent it?

If anyone has any other suggestions on designs using these elements, I would be very interested in reading them.

My thanks everyone's patience in reading this,
Susan
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