Cat Eye Crucible

[wvrons]

Below are pictures of a piece of equipment which Vitro used in making cage style cat eye marbles. This was dug from the river bank near the Vitro factory in Parkersburg WV. It is broken, not whole but you can see how it worked. 

Some will label it a crucible. A vessel of refractory material used for melting.

Some may label it a injector. Used to introduce a factor or something into a object or place. 

Some may label it a color pot.  These were usually a bowl shape in the upper part of a glass furnace to add color. 

It is made of special refractory brick material to withstand the heat.  It is long cylinder tube or pipe shape. It was located inside the glass furnace near the front outlet. Colored glass was added to the compartments of the crucible.  These were in a circle shape at the outlet holes.  The crucible was cut to have V shape large grooves were the clear base glass flowed to the furnace outlet. The clear base glass flowed around and down the V grooves of the crucible. The colors flowed down the inside of each hole through the crucible. The colored glass flowed into the clear glass with clear glass flowing all around and encasing the colors.  The hot glass stream then quickly exited the furnace to the shear. The one below is about 6 1/2 inches wide and could have been two feet or more long. Depending on the size of the furnace. The one below was for six color streams. These could be six different colors or all the same color or mixed. Crucibles wear out or fall apart fast. Usually faster than any other part of the furnace. It is possible to change out one while the furnace is loaded or in operation. But it is not easy and dangerous. Replacing one usually means a shut down.  Which any shutdown is hard on everything.  As the clear and now colored hot glass stream would flow out the furnace exit and down to the shear. The colors would thin and get wider making what we call a vane.  Most times the colors ended up centered but sometimes the color would get off to one side of the clear. This can be from flow, or temperature.  With the Vitro cage style Cat Eye the color or colors were twisted or swirled. This was probably done with a longer hot glass stream to the shear. The longer stream has more time and length to turn and twist as it falls. Like many WV swirls and most Jabos are made.  Then the elongated hot glass stream is sheared twice and then the glob falls down a chute or tube to the marble machine were the hot glass glob is rounded into a marble.  All the pattern style or type of marble being made happens upstream before the marble machine. The marble machine makes it round. 

Picture #1 

Looking at the bottom of the crucible which would be pointed down near the furnace outlet. 

 

#2  Looking at broken crucible from the top or end that would be towards the top of the furnace.  The cuts or grooves on each side of VITRO is where the clear glass would flow. 

#6 From the side and the bottom where the colors would meet the clear base glass. 

 

#8 

 Close up where you can see the broken refractory. 

 

Not easy or short to explain in words. Maybe with the pictures you can have more of a idea how color was added to make Cat Eye marbles. The above is just the basics. Crucibles can be made in different configurations and sizes. Crucibles are just one method or way to add color to glass machine made marbles.  

[Tommy]

Thank you Ron for the effort to bring this incredible information to everyone👍..this is great info . 

The pics make it all come together 

[Ric]

That's a great relic, Ron. Thanks for sharing!

[Steph]

Such a big piece to make such tiny details in the cat's eyes.

Fascinating.

[akroorka]

Great work once again Ron. 
Thanks for all of the effort and time that it took to put this post together.

Great stuff!
Marble—On!!
 

[Dave 13]

Thanks Ron , the information you share with us is much appreciated in the marble community 👍

[chicagocyclist]

Wow, so awesome.

[Carowill]

Ron, you’re a national marble treasure!  Thank you for your willingness to share your knowledge and exu!

[Carowill]

Experience 

[wvrons]

Thank you everyone. I had help along the way from some special people. Just sharing as possible same as they did. 

Thanks to Mike Johnson who supplied this crucible. I have a few others from other companies, including a four vane from Vitro. All  that I have seen had even numbers of holes for color, 2-4-6. But we find five and seven, etc, odd numbers of vanes and colors for especially Vitro cage cat eye's. Probably when a six hole had one hole plug, they still used it and then had a five color or vanes, not six.  Crucibles were used some at Jabo before and during the special investor runs. Crucibles are not used for only clear base glass. They are also used with opaque base glass. But they would not last long at Jabo. To high of a temperature for to long or wrong type refractory and they break or fall apart. Probably lots of the furnace brick seen inside marbles could be from a crucible. Crucibles are only one method or device used to deliver color. Refractory sloped slide chutes have been used to delivery color. Refractory pots of different sizes and shapes have been placed inside the furnaces to delivery colors. Large operations also had colors in a separate small day tanks(furnace)which was then fed through refractory to the main furnace with the base glass. These small color tanks could be near the main furnace or several feet, twenty or forty feet away. These sometimes could feed more than one base glass furnace at the same time. Adding colors was always changing and something new developed every few years. 

 The bottom line with machine made marble production was always number of marbles per minute. 

[chicagocyclist]

I have given prize symbols to all this information.  It is truly astonishing that with all of those requirements, all of those difficulties, all of those practicalities that they were able to produce such incredible things at such an amazing rate. We are truly grateful to have this information available to us, to know how it was done. So many How'd They Do It things in past history have lost.