Metal insignia are generally small enameled pins denoting branch of service, unit within a branch or some type of accomplishment by the individual.  The word insignia is Latin in origin and means “to mark upon” or “to distinguish by marking”.   When dating metal insignia from the military the front of the insignia does not provide much information.   Turning the insignia over and observing how the insignia attaches on the reverse side, however, will offer a good foundation for dating the item.

The different variations of attachments used on metal insignia have undergone a steady evolution.  The earliest mode of attachment was simply prongs soldered to the back side of the insignia pin.  Insignia with this form of attachment date back to Civil War and post-Civil War time.  Another form of attachment commonly found from this era is the use of a single wire loop, also soldered on the back.  This form of attachment allowed the metal insignia to be sewn or pinned into place.

Insignia were originally stamped out of sheet metal.  But prior to the Spanish-American War this all changed when the insignia began to be cast.   The casting method required a new attachment method since it did not have an indented area to allow room for the pooling of the soldered metal.  Several means of attachment evolved at this time – screw back, hinged pin modes and latched pin modes.  Hinged and latched pins underwent an additional change prior to WWII.  At that time, a locking device was added to the catch.

The last major change for metal insignia attachment took place in 1942 when the Ballou fastener was introduced.  This particular fastener belonged to a class of fasteners known as clutches.  The body of the Ballou fastener would slip over the pointed post and lock into place.  Removal of the insignia simply required the depressing of the two arms on the side of the body of the fastener.  The Ballou fastener has undergone some changes as well since it was first introduced, which makes it more difficult to date as the original fasteners have often been removed and replaced with others.

Careful inspection is required when dating metal insignia of the military in order to ensure accurate validation of the time frame of each piece of insignia.

Below are some examples of the various backings that can be found on metal insignia from the military.