However, in the 1960s and 1970s an inquisitive, stone-loving, college dropout named Don Crabtree rediscovered a method of making Mesoamerican obsidian blades (so-called prismatic blades) that he claimed were sharper and more precise than surgical steel. Today, most people know obsidian as a material with ornamental value, or as a material that represents ancient times and weapons. These metals were far easier to obtain, work and shape than obsidian, 12 and they were used in tools that ushered the world out of the stone age and brought about more advanced society. 11 It’s evident from the vast distances that obsidian was moved that ancient cultures defined the glass as a precious commodity, with tools and weapons crafted from obsidian being extremely valuable assets.Īs cultures learned to smelt copper, and later bronze, the value and use of obsidian decreased significantly. It is through this fact that historians are able to know that Mesoamerican tribes (the indigenous cultures occupying Mexico and Central America prior to the Spanish conquest) transported the material in great quantities across the length and width of the peninsula, and, in the South Pacific, some tools were transported distances of nearly 2,000 miles over land and sea. Essentially, each sample carries a specific mixture of trace elements that is unique to the volcanic activity in which it was formed.
Historians have discovered that obsidian was a highly traded commodity, and have been able to map out trade routes thanks to the material’s unique fingerprint. Cultures that didn’t have access to the cooled lava flows traded other valuables to secure obsidian for their own societies. Its characteristic sharpness allowed its use in nearly every cutting instrument imaginable: axes, arrowheads, swords and knives. Put simply, it’s brittle, and the pieces that flake off have a uniform, ultra-sharp edge. The lack of crystal formation results in a material that is significantly isotropic and homogenous - qualities that generate benefits for which ancient peoples prized obsidian. The nature of the lava, being both viscous and polymerized, prevents the diffusion of atoms during cooling, leaving behind a glass ceramic that’s unable to form a crystalline structure. Obsidian is formed by the rapid cooling of silicate-rich lava.
In Africa, the Middle East, Eurasia and the Americas, ancient peoples used the material for tools, weapons and decoration, and in bartering, long before the advent of metallurgy. 7 There, researchers found caches of obsidian blades and discs, and even an ornately decorated chalice. at a site called Tell Brak in Mesopotamia, which is reportedly one of the world’s first cities. 6 The first attested urban use occurred in the fifth millennium B.C. With an average flexural strength five times that of conventional ceramics, 3 Obsidian is a reimagining of proven restorative technology.Īrcheologists suggest that volcanic obsidian was used by cultures around the world, with scholars finding evidence of use as far back as 700,000 B.C. Some of these indications include: bridge cases that lack the vertical dimension necessary for zirconia connectors cases where the restoration must match PFMs located on the proximal teeth and restoring endontically treated teeth that have crown or root staining that would bleed dark shadows through all-ceramic restorations.Įnter Obsidian lithium silicate ceramic, a natural-looking, state-of-the-art ceramic material that can be pressed to a metal coping to create the strongest and most esthetic PFM. Though the data found by major research organizations and countless clinical successes have proven the benefits of monolithic zirconia, 1, 2 there are still a limited number of indications for which zirconia is not the most ideal restorative material. Some have asked us at Glidewell Laboratories why we - the championing lab behind the monolithic revolution and BruxZir ® Solid Zirconia - would take a seemingly backward step and tell them to start prescribing PFMs again. Clinicians across the United States have been intrigued about the release of Obsidian ® Fused to Metal.
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