A little known fact is that the old luminous paint was mildly radioactive--actually, a form of radioactive cobalt and/or radium, mixed with phosphorescent paint. The newer material is an acrylic material consisting of a long-persistence phosphorescent material, sensitive to photons (light). Whenever I give a manufacture date on a Westclox product, it is actually a date stamped on the movement that gives the month, day and year.
Remember, a peg leg Big Ben from 1915 only cost .50 when it was new. ), it was not intended to be a precision instrument.
* Investment: some people buy to collect and increasingly, good quality vintage items especially items by well-known designers are sought after by collectors.
Retro is a word used to describe, denote or classify culturally outdated aged trends or fashions, from the overall postmodern world, but have since that time become functionally or stylishly useful once again.
In North America, the term can be used as a synonym for a "rummage sale", to describe charity fund raising events held by churches and other community organizations, in which donated, used goods, such as books, clothes, and household items are sold for low prices, or else the goods may be new, handcrafted or home-baked, as at a church's Christmas bazaar.
* Unique or almost unique - some items were custom made, and others were manufactured in small quantities.