Day 280-Cobalt (or Sapphire)
The “Orange Ball or Square B” label was used from 1983 until 1999. Sapphire was made until 1989 and Cobalt started in 1990. Going by the label alone it is impossible to guess which color this is. However, this bottle does not have a raised ridge bottom on it and we know that the raised ridge was replaced sometime before 1991 because no one has seen an Amethyst or Emerald raised ridge water bottle, both of these colors being introduced in 1991. Plum was made in 1988, 1989 and 1990 and comes in both raised ridge and non-raised ridge varieties so we actually know that it was sometime in 1990 at the latest. However, it is possible that the molds were changed as early as 1988. If this were the case, then Sapphire could have been made for 2 years MAXIMUM without a raised ridge bottom and Cobalt would have been made for at least 10 years (1990-1999) with this label. So it is 5 times more likely to be Cobalt than Sapphire.