 Hi, I'm Scott and I'm on the production team that makes art resin at our facility in Dallas, Texas And I've got a resin tip for you Just like most art materials art resin has a shelf life art resin shelf life is 12 months unopened and six months once open from the Data manufacturer you can find a manufacturing date on every bottle of hardener to make it easy to track how fresh your art resin is Art resin shelf life is shortened once you open it because of oxidation when you open the bottle The hardener comes into contact with oxygen in the air which creates a yellowing effect Just like an apple that browns once it's been cut if you find yourself with some expired product on your hands Please don't toss it in the trash. It'll still cure the same way Check out our blog. What can you do with yellowed hardener for lots of ideas on how to use it? And that's your tip for today. Thanks for watching