Marmalade. Which side of the plastic circles has wax on?

[2rebecca]

I've made jam and marmalade for years and use the waxed circles. All the advice tells you to put them waxed side down but nowhere (and I have Googled it) tells you if this is the rough or the smooth side.
Sometimes I think it must be the smooth side because candles are smooth, other times I think the wax is maybe rubbed on and has a rough texture.
I presume everyone else knows. Please put me out of my misery.

I've never done it myself, but just checked a WI feature in Prima magazine and that says smooth side down. HTH!

Thank you.