Dear members,

I would like to publish my experiences as an amateur of this newborn art;
You all know those little aluminium cans which hold tiny, flat, white candles (or teaheaters).
well, i tried to align these cans in my backpack at the airport, I even had some people ready to shoot a photo as the bag was lit under the Röntgen-ray, but unfortunately, this material was proved unsuited twice during my trials.

So, what are the X-ray captive materials that we should use, fellow amateurs?