Gems are easier to get and use than stars. Gems, you can mine and get by completing goals, and spend them on furniture, food, and some bunnies! Small Goals give you small amounts of gems, big goals give you large amounts, and really big goals that take a long time, like collect 1000 bugs or something, give you stars. Here are some gems you can mine! Sapphire(blue)Emerald(green) Ruby(red)and Diamond, which is white. You can place one bunny on a Sapphire, two on Emerald, three on Ruby and four on Diamond. Stars are harder to get. You can use them to buy some furniture, purple carrots and most bunnies. The most expensive thing that costs stars is the Albino bunny same with angler. On some goals you can win stars BUT those goals usually take a long time and are a lot harder. Big star goals give you more stars like 7 or 5 or higher.
Luck and Miner 49er bunnies are the best miners, whereas Albino and Angler are some of the slowest miners, sadly. Also, as you probably know, all gems have their limits. Sapphire's is 500, Emerald's is 1000, Ruby's is 5000 and Diamond's is 10,000. When your bunny is finished they will read a book on the gem's edge and wait for you to collect the gems, then they will start mining again.
The bunnies get tired and stop mining. Place them on a bed or chair or feed them, and they will continue to mine. The more their energy bar is filled, the more the bunnies mine!