These have the same silhouette as the Blenko water bottle but there is a flower (I have seen it described as an orchid or an Iris.) where the indentation should be. So far I have four different colors. Tiara’s name for these colors were Ebony, Amber, Sunset and Crystal. Tiara made at least 40 colors so it will be interesting to see if any others show up. Each of these are marked Tiara in script on the bottom. The pattern name is Regal.
Tiara was started as a glass merchandising company by Indiana Glass in July of 1970 and went out of business in November of 1998. Indiana Glass made the bulk of the glassware but some pieces were produced by other glass houses (i.e. Fenton and L. E. Smith.) They were sold exclusively through home parties at the time. Black and Amber are the most common color for this water bottle. I suspect that there are fewer Crystal water bottles to be found because they were not big sellers and therefore fewer were made.
Update June 30, 2012: Internet searching as provided me with more information, as follows. The Ebony water bottle was introduced in 1975 and has an item number of 10015, the Crystal water bottle was introduced in 1976 and has an item number of 10012 and the Amber water bottle was introduced in 1977 and has an item number of 10068. There was no information regarding the Sunset water bottle on the site.
Update July 11, 2012: Ebony, Amber and Crystal water bottles were offered to the public at home parties but the Sunset Water bottle was not. It was probably made in limited numbers and offered as a premium to the Hostess of the parties.