The test for die cast is a two part process:
1. Put a magnet to it. If it sticks, it's not die cast or aluminum.
2. Have some water handy. Take a drop of battery acid and drop it on the part in an inconspicuous area. If it bubbles, it's pot metal (die cast). If it doesn't, it's aluminum. Drench with water to stop the acid attacking the metal further.
To get an antiqued look, you can replate die cast with our Flash Copper Kit, then use one of our antiquing solutions on the copper plate. You can also brass or bronze plate it, after copper plating.
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Plating Kits Chrome Plating Kits Aluminum Anodizing Kits Electroplating Kits - Caswell Inc.