You never know what you’ll find at the nursery or a thrift store that will be perfect in the studio. These metal planters are a great solution for storing heavy, sharp sheet metal. They’re durable and some have handles that make transporting heavy metal from one place to another much easier.
I’ve used mine for years and years, and they’re still in great shape (even after a cat peed in one of them and “patinated” both the planter and all the metal in it). If you buy the type with handles, make sure that they — and you — are up to carrying a lot of weight.
If they ever get a little rusty, you can sand the rust off and then use a sealant (brush or spray) to prevent the rust from returning. Some come with plastic liners, though they won’t last long when storing sharp metal.
You wouldn’t want to store precious metal this way, but for non-precious alloys, it’s a very good solution.