When you reach Lesser Zone make your way east from the Boiler House, you'll notice some wooden planks blocking a cave entrance thats your target right there. The Magnetic Cave can be tricky to navigate with all those flame anomalies, but getting the Spinner artifact is worth the trouble. Look for an explosive barrel near some crates, shooting it reveals a hidden chamber that you need to check out. Your detector will start going crazy near the left entrance wall, and thats where youll find the Spinner, giving you some nice bleeding resistance and worth a solid 7500 Coupons if youre looking to sell.

Just remember to watch those flame spots carefully, maybe bring some protective gear since the cave gets pretty hot. The explosive barrel trick is actually pretty useful, and youll find similar setups in other areas so its good to keep an eye out for those. Getting through the wooden planks is your first challenge but after that its mostly about careful movement and watching your detector readings.