What we know is more of the 25s and 100s were ordered in the early 2000s. Much like the blue bud jones 1k has some variation the green
thc 25 has some. My speculation is different clay from different runs. I think the difference is in the clay color not spot patterns. I am not sure if the darker clay was from the earlier or later run. I have seen chips in excellent condition of both colors. Maybe
@Windwalker has more examples than me and can draw conclusions. About which was which. My best guess is darker was earlier