Whirling Hobstar Vases, Fenton
These are Fenton's number 8654 pattern. Fenton does not give it a name so I've chosen one used by collectors. The cobalt with marigold iridescence example on the left was introduced in 1984. These are generally worth $20 to $30 on eBay. A green example sold on eBay in 2012 for $40 (Buy It Now). The red example sold in 1997 at live auction for $63.

In 2021 an 8-inch vase in ice blue sold for $50.