Even though Coins are used as in-game currency, Diamonds are the form of currency Hay Day players value the most. You can pay for Diamonds with real-world money, but you can also get them in other ways.
For example, you get one Diamond for following Hay Day on Facebook, while logging in to Facebook using Hay Day gets you 5 Diamonds.
Mystery boxes, achievements, and competitions organized by Supercell on their Facebook page will also get you this precious resource.
Finally, once you reach Level 24, you can also mine for Diamonds.
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