Red glass might come from recycled iron furnace slag. While the  
typical color is dark green or blue, there is at least one furnace  
that has a really nice ruby red glass from the incidental chemical  
inclusions in the ore. The stuff was recycled into usable products so  
insulators would be a reasonable item. Time to do some chemical  
fingerprinting if there's one to be found and tested.

Lyle Browning


On Aug 8, 2007, at 9:00 AM, geoff carver wrote:

> there is a good collection of the australian ones at the pitt- 
> rivers museum in oxford; i don't remember any red ones, though,  
> just transparent green & white, and translucent white; how common  
> is red glass anyway, especially red glass insulators???
> ----- Original Message ----- From: "JAMES MURPHY" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Wednesday, August 08, 2007 2:53 PM
> Subject: Re: Glass Insulators - Myth or Truth?
>
>
>> I've heard the story in re: Australian aborigines.