Antimony Throwing Dagger
When the daggers are embedded in any magical field or shield, they begin weakening it, until it eventually collapses. The time needed to destroy a shield is variable and depends upon the strength of the Thaumaturge that creates it.
The daggers may be set alight, without damaging them, but they only burn for a short time. This does cause additional aggravated damage to those affected. they can also ignite flammable items.
The items are enchanted to allow this latter function to be used.