Who created the first Ancient functional art vessels?!

It was the innovative glassmakers of Mesopotamia (modern-day Iraq) who developed the Core-Forming technique (also known as ’sandcore’) in which vessels were created by trailing decorative threads of molten glass over a core of sand, mud or clay.

Once the glass was in place, threads of glass were dragged into decorative patterns such as waves, garlands, arches, and leaf or feather designs.

To demonstrate, here are images that show the stages of Ancient CORE-FORMING.

The core mixture is created by mixing clay with vegetal remains and sand, shaping, drying and firing the core to about 1000°C. A lump of the core material is attached to the end of a metal rod, shaped by hand, and rolled on a flat surface.  Glass of contrasting colour to that of the body is applied by melting the tip of a pre-formed, thin rod, attaching it to the vessel body and turning the vessel to wind the rod around it. Over the furnace, the trail width is controlled using the heat and by varying the turning speed.  

The trails are melted in and feathered.

  The finished vessel, still on its core and rod, is annealed, a process of slowly cooling glass to relieve internal stresses after the glass is formed. When cold, the rod is twisted free and the core carefully extracted.

With appreciation to glassmakers Mark Taylor and David Hill. 

Photographs courtesy of Paul T. Nicholson.

Making glass in these early days was slow, difficult and expensive. Furnaces were small, the clay pots were not of good quality, and it was difficult to generate sufficient heat for melting glass. Centuries would pass before glass would possess the clarity and transparency that we know today.