When it can be steel or aluminium, you could judge using the density. When the cups have approximately the same size and weight, the aluminium one has to have walls that are three times as thick as the walls of the steel one. That should be easy to determine.
_________________________
If it isnīt broken, it doesnīt have enough features yet.
WARNING & DISCLAIMER:
SELECT AND USE OUTDOORS AND SURVIVAL EQUIPMENT, SUPPLIES AND TECHNIQUES AT YOUR OWN RISK. Information posted
on this forum is not reviewed for accuracy and may not be reliable, use at your own risk. Please
review the full WARNING & DISCLAIMER about information on this
site.