What variety is this? If the colors are dark blue-ish, then it may be antho expression. Have you seen the tomatoes with dark/black colored shoulders that are starting to be sold lately?
Even if yours is not supposed to have the antho gene, I hear it is rather promiscuous and the pollen may have snuck in via wind or accidental bee cross, especially with home saved seeds where no effort for exclusion was made (bagged blossoms, etc.)
Here is a collage of some of the varieties I'm growing this year with more extreme forms of foliage antho expression:
Here is one fruit with beginning of fruit antho expression:
The antho pigment is like the plants' version of melanin that causes freckles and tanned skin and show up more and darker on the fruits when exposed to sunlight, but on the the foliage, the color shows up more and darker when the plant is exposed to cold temperatures.
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