Some cows just give really thick cream! Consider yourself lucky. Unless it's soured and that's why it is so thick...
In my experience, when the cream initially rises to the top of the milk after 12 hours or so, it's the consistency of storebought cream. Let it settle a few more days and you'll get less cream from the top (the creamline shrinks), but the cream is more concentrated - thick enough to stand a spoon in.
If the farm uses a cream separator, they can change the setting to produce thinner or thicker cream. They might have set it to put out only the very heaviest cream, with a very high butterfat content.
You can thin it out with some milk.