Revelation 6:5-6

5Then the Lamb opened the third seal. I heard the next being say, ‘Come!’ I looked, and I saw a black horse. The person who was riding the horse held something in his hand. He used it to weigh things.

6Then I heard a sound like somebody speaking among the four beings. The voice said, ‘A litre of wheat is worth one day's work. And three litres of barley is also worth one day's work. But do not destroy the olive oil and the wine.’