Dragons don't have martial weapon proficiency and in an Anti Magic Field, it's little more than a masterwork weapon, especially in the hands of someone without the Weapon of Legscy features. He'd be better off just clawing Bloodfeast.
Correction: Dragons don't default to having weapon proficiencies. Calder could have taken short-sword proficiency as a feat (adjusting for size, that's what it is), which would enable Calder to us it in grapple, trading one of his D6 claws for a 2D6 huge shortsword.
The thing is the Azurites don't use a single color; they use a single hue. The use light blue, dark blue, black, white, glossy blue, off-white with a bluish tint. They sky's the limit, as long as it's blue.