Was Jesus robe scarlet or purple?

Why does it state in Matthew 27:28 that they put on our Lord “a scarlet robe” and in John 19:2 “a purple robe”?

Are the references to the same garment, and if so, why are they said to be of different colours?

I do not think it is possible to evade the difficulty by maintaining that the reference is to two different robes, for in both cases we read that those who thus clothed our Lord in mockery were the soldiers present at the trial, and the circumstances are the same. But the word translated, “robe,” is not the same in the two passages. That employed by John is quite a general word, rather like our word “garment” or “clothes,” whereas the “Matthew” word is particularly used for an official military cloak. Some such old uniform might, as has been remarked, be easily found by the soldiers in the Pretoria or barracks, and would be scarlet, the usual colour worn by high Roman officials. Here the word for “scarlet” (kokkinë) is a very definite word. The word translated “purple,” on the contrary, is very indeflnite. We might almost say that the “John” word could be adequately translated “bright colour,” while the “Matthew” word gives the exact tint—scarlet. We may add that the word translated, “gorgeous,” in reference to the robe (again another word) in which Herod arrayed our Lord (Luke 23:11), does not specify its colour, but rather its brilliancy; it was probably made of some tissue of metallic lustre. I do not think it the least probable that this was the robe in which the soldiers dressed our Lord; it would be very unlikely that they would have access to that. It seems to have been rather a gift worthy of the acceptance of Pilate, and indeed a feeler for his friendship. Thus are the quarrels of the world patched up in a shallow and unrighteous fashion, but the hatred at the bottom of the heart remains.