Topic: ID help please

[millarart]

found this small weight in a charity shop yesterday i have no idea of maker and there are no marks / signatures etc anywhere on it , the thin ground is very dark purple , seems to have an opalescence look to some of it , measures around 1.75 across and just over an inch high ,

[millarart]

i have since found out that this style of glass is called borosilicate

[chopin-liszt]

Borosilicate glass is what Monax is made from Gary. The lab ware. It's somewhat heat resistant and the older stuff used for Monax was not a terribly good colour. (yellowy)
It is currently popularly used for lampwork and beadmaking, and checking, i find the colour is better now and it can be made other colours.

Your weight is bothering me. I can't work out if silver salts have been used or not. They can give rise to a somewhat opalescent/iridescent appearance. Silvery blues and yellows fading in and out, and sometimes a hazy sort of electric blue in the metal.

[millarart]

yes sue i have looked up all about it , if you google Borosilicate glass paperweights /marbles you will see several same idea as mines and is used to make the small coloured tubes and rods  for lamp work use in weights like mines etc  =In lampworking
Borosilicate (or "boro", as it is often called) is used extensively in the glassblowing process lampworking; the glassworker uses a burner torch to melt and form glass, using a variety of metal and graphite tools to shape it. Borosilicate is referred to as "hard glass" and has a higher melting point (approximately 3,000 °F / 1648 °C) than "soft glass", which is preferred for glassblowing by beadmakers. Raw glass used in lampworking comes in glass rods for solid work and glass tubes for hollow work tubes and vessels/containers. Lampworking is used to make complex and custom scientific apparatus; most major universities have a lampworking shop to manufacture and repair their glassware. For this kind of "scientific glassblowing", the specifications must be exact and the glassblower must be highly skilled and able to work with precision. Lampworking is also done as art, and common items made include goblets, paper weights, pipes, pendants, compositions and figurines.

In 1968, English metallurgist John Burton brought his hobby of hand-mixing metallic oxides into borosilicate glass to Los Angeles. Burton began a glass workshop at Pepperdine College, with instructor Margaret Youd. A few of the students in the classes, including Suellen Fowler, discovered that a specific combination of oxides made a glass that would shift from amber to purples and blues, depending on the heat and flame atmosphere. Fowler shared this combination with Paul Trautman, who formulated the first small-batch colored borosilicate recipes. He then founded Northstar Glassworks in the mid-1980s, the first factory devoted solely to producing colored borosilicate glass rods and tubes for use by artists in the flame. Trautman also developed the techniques and technology to make the small-batch colored boro that is used by a number of similar companies.[17]

[chopin-liszt]

  This should all help to date it and confine it to a certain group of makers.
I really love it. It looks like pebbles from Lunan Bay, under water from the top, but multicoloured rainbows from the side.

[Fuhrman Glass]

These are not easy to identify as there are literally 1000s of lampworkers in the U.S. making all sorts of items from borosilicate glass. The younger generation has developed the market for pipes and smoking accessories and there are now shops making huge production of some items. There has also been an explosion of lampworkers now working on glass lathes and creating some very nice stemware, bowls, jars, and other items . Traditionally these were just used for making scientific labware but now there are 100s , maybe 1000s, in the U.S. alone that are using these lathes for production of all kinds of items. The legalization of marijuana in many places has given rise to the development of all kinds of apparatus for smoking that lampworkers have been happy to create for this market. I recall seeing one pipe go at auction a year or two ago for in excess of $90,000. Corning has now just included some "pipes" in their recent New Glass Review, a yearly contest of the best and newest art glass in the world.

[tropdevin]

Fuhrman Glass...exactly ...easy for thousands to work with.  Boro ( ie  Pyrex) does not need careful annealing.

Alan

[chopin-liszt]

 
So; date is contemporary, and the number of potential makers is in the thousands.
It did help pin things down...