I've found the difference between olive amber and olive green to be quite subtle. In fact, the differences essentially disappear in a backlit display cabinet. In the sunlight, however, the differences can be seen.

I've shown here an olive amber Star beehive on left followed by an olive amber NEGMCO beehive in the middle. The olive green NEGMCO beehive on the far right was from this year's 2005 National. Hopefully the differences between these colors is apparent.