Ok, so plaid can be any material that is basicly a blanket that can be worn as a robe or skirt of some kind. Oops, I said the "s" word.

I'm not so worried about whether it feels like a synthetic material but what it does when it gets hot. It melts... to your skin. Besides being a waste of money for a nice kilt that will be destroyed, just like any other non heat resistant material, it would have longer lasting problems than just leaving you with out a kilt on. If I can't find a practical, heat resistant material that will withstand scale and the odd ember bouncing off of it (or sometimes sticking to it), then I simply won't wear it near a forge.

The scale itself is not THAT hot by the time it lands on something. When it hits my arm the pieces are really small, like a millimeter across, and so it only leaves a small welt behind. The kilt might be a bit more exposed to the scale than my arm due to how low it is.