LEED and other recent environmental initiatives have increased the construction industry's awareness of recycled content in building materials. However, finding alternative uses for industrial "waste" is not a new concept. This is made clear by recent archeological excavations in London that reveal how the bone core of horns were used as masonry units.

After the Romans settled in today’s London, Aldgate surroundings (eastwards from the city wall) were turned into a cemetery. But in the Post-Medieval period, Prescot Street was transformed from an essentially rural situation on the fringe of the City, into a densely populated central district. Among the on-going archaeological excavations at this site, a horn core pit has been discovered, showing the intense industrial activity in the area.

The pit itself consists of a cylindrical void with a perimeter structure built with animal horns as a cheaper alternative to bricks. These kind of industrial memories are often found in areas known for small-scale industry, such as ivory-working, tanning, bell founding and glass making.[...] These pits are sometimes used as soak-aways.” (www.deconcrete.org/2010/10/30/horn-walls/)

Underlying the basement slabs were large deposits of Post-Medieval soils that had been truncated by two large soak-aways and one small, and a horn core pit constructed from the horn cores of long horn cattle. This is significant because ‘horning’ was once an important industry in the area... ‘Horners’ were skilled craftsmen who worked horn from cattle to create a range of artifacts from drinking vessels to buttons, and from panels in lanterns (when sliced very thinly) to tool handles.

The waste from this procedure, the horn core, was not discarded, and was frequently reused as a lining for round pits with vertical sides dug deep into the ground. The horn cores were inter-woven to offer a degree stability to the structure, and the pit was then used for the disposal of domestic waste. They essentially performed the same function as the soak-aways, with waste material being dumped into them so that the waste water would drain away into the natural gravels below, while the remaining solids were broken down over time by bacterial action. (www.lparchaeology.com/prescot/journal/field-officers-report-for-week-ending-28th-march-2008)

What would it take to get an ICC-ES Evaluation Report on such a construction material today?

Photos from www.lparchaeology.com/prescot/galleries/photo-diary-for-25th-march-2008/set/72157604245105892.