So we have a special jar for mustard called . . . 3 1/2oz mustard. Now as very few people refer to jars by their Imperial Ounceage we now know it as the 105ml classic.
Suitable for mustard? Meh, not so much - I would say that it is too fiddly to fill with mustard. Herb or fruit jellies would be my choice and would look very pretty as wedding favours. Plenty of room for a label and some decoration as well.
Moving up through the lid sizes this little jar takes a 48mm lid in a choice of black, gold or silver
There are recipes for making herb or fruit jellies in my
Recipe Website
JJRD-105M