Lime

Is there a difference between hydrated lime and agricultural lime? They LOOK different. Thanks.

Agricultural lime is a very loose definition. It can refer to ground limestone (Calcium Carbonate) , ground dolomite (calcium magnesium carbonate) or hydrated lime (calcium hydroxide). Hydrated lime is very quick acting and also caustic.

Thanks. I asked the question as I was using up an old bag of hydrated lime. The replacement was labeled as agricultural lime and the texture is very different. May I assume gypsum is another animal?

Yep; Gypsum is calcium sulphate