Creating a glass vase is a very complicated process which must be done very quickly or the glass will cool and harden. Each color of glass needed is put into a burner which melts it so it can be sculpted. The glass blowers use long poles to roll layers of glass together. The tubes are hollow so that they can blow into them to create a pocket which will be made into the opening of a vase or bowl. Sometimes, little shards of brightly colored glass and foil are sprinkled onto the piece as it cools. This adds extra flare to it.
 
 
 
 
This is a perfume bottle. The bottle is made of many colors and layers.
This is a glass paper weight. The inner flower is extremely difficult to make. I have never seen it done myself.
This is a vase that was made similarily to what the first papagraph above describes. As the artist blew into the tube, the opening in the vase was created. When the glass cools, the artist will hit the end with a hammer to break it off from the tube. They have to be very carefull when disconnecting because they could break what they were working on.