The Greek that is translated as “purple” in English is translated as “blue-red” in Ojitlán Chinantec.
In Kasua was a little bit more involved, as Rachel Greco recalls (in The PNG Experience):
“The Kasua people of Western Province have no word for the color purple. They have words for many other colors: black, red, white, yellow, green, and blue, but not for the color of royalty.
“About nine New Testament passages mention people placing a purple robe on Jesus. The Kasua translation team always wanted to use the word ‘red,’ or keyalo, to describe the robe. Tommy, one of the translation team helpers, disagreed because this is not historically accurate or signifies the royalty of Jesus.
“One of the main rules of translation is that the team must stick to the historical facts when they translate a passage. If they don’t, then how can the readers trust what they’re reading is true? Other questions about truth could bubble in the reader’s minds about the Scriptures. For this reason, Tommy was not willing to change the word purple. So the team hung up the problem, hoping to revisit it later with more inspiration.
“God did not disappoint.
“Years later, Tommy hiked with some of the men near their village. They saw a tree that possessed bulbous growths growing on the side of it like fruit. These growths were ‘the most beautiful color of purple I’d ever seen,’ explained Tommy.
“’What is the name of this tree?’ Tommy asked the men.
“’This is an Okani tree,’ they replied.
“Tommy suggested, ‘Why don’t you, in those passages where we’ve been struggling to translate the color purple, use ‘they put a robe on Jesus the color of the fruit of the Okani tree’?
“’Yeah. We know exactly what color that is,’ the men said enthusiastically.
“Everyone in their village would also visualize this phrase accurately, as the Okani tree is the only tree in that area that produces this kind of purple growth. So now, among the Kasua people, in his royal purple robe, Jesus is shown to be the king that he is.”