Amber was not run continually, but was brought back as orders warranted. Several of the Heisey animals were made in amber and are very desirable. There are also some stemware lines that have amber bowls or stems. Black Black opaque was an experimental color and was never expanded for consumer use. It is considered unusual for a Heisey color because it was produced in a limited supply.
Pastel blue is thought to be an experimental color made for special orders or testing on the market.
This color is similar to some shades of Limelight or Zircon, but it has more of a blue tint. It, too, is in limited supply. Albemarle 5 oz. This glass will glow bright yellow under a black light. The pieces will usually be accessories, such as vases and compotes.