Focus on Mound of Butter and explore the Painting.
The painting is a great example of Vollon's still life art, depicting a mound of butter, coloured in rich, deep yellow colour (presumably from the carotene of the fresh plants that grazing cows commonly eat on barn fields). At the time when Antoine Vollon lived, it was usual to purchase the butter from the farmer, handmade. 
Typically, after milking, the cream is to be collected, churned and the butter lumps are kneaded by hand or worked with a spatula to get rid of the moisture from it, because the high amounts of buttermilk would shorten its storage life. Back then, butter was usually stored wrapped in a cheesecloth, in a cool place. In the painting, the butter mound's cloth is falling loosely over a couple of eggs beside it.The painting also has thick marks layered on top of the artist's brush-work, probably meant to illustrate the marks after the butter knife was used to spread butter with; or the wooden spatula, used to spread the butter with and also used in producing the butter. Kitchen scenes, food preparation, and depiction of everyday objects were a usual subject for still lifes in Vollon's time.
still life barn fields moisture kneaded storage life cheesecloth egg cows grazing spatula carotene butter knife wooden butter churned food preparation Antoine Vollon brush