According to The Royal Order of Sartorial Splendor who sites Suzy Menkes, Queen Alexandra had the opals in the earrings and necklace (along with the Oriental Circlet) replaced with rubies in 1901 and 1902 but the brooch was not changed until 1926. I definitely see a difference in the gold prongs holding the rubies, they are much larger on the earrings and necklace. As for the color, I looked through the pictures again and in some of them the rubies look different colors and in some they look the same. I think part of the problem is that the brooch is worn over the red sash.