Materials

These transparent gypsum crystals were known in ancient times as ‘Lapis specularis’. Lapis specularis is crystallized gypsum which the Romans used for their windows.

The crystals allow the light to pass, hence the Latin name: ‘Lapis' (stone) and 'speculo' (mirror).

This mineral was the economic engine for an entire region in Hispania (Spain) for almost a century and a half. This economy collapsed when a technique was invented to make larger rectangles from glass.

Here is a small selection of the available minerals & crystals: white opal (described by Pliny the Elder), citrine (very expensive in antiquity), red jasper, blue agate, amethyst, sodalite, aquamarine blue, ...

Naturally formed crystals grow in different shapes, colors, shades of color, ...

In antiquity these stones were used for jewelry, dye, raw material, healing properties, ...

Obsidian (volcanic glass), millstone, flint/silex, horn, bone, a piece of meteorite from the Kamil crater, copper, iron, ivory from a mammoth (10.000 years old, from the permaforst in Yakutia, Siberia), ...

The first Greek word for iron is ‘sediros’ (= of the stars), because the first metal objects were produced from meteorites, which contain a lot of iron.

Antlers and horns of animals were used to make tools.

This piece of obsidian was found in an ancient workshop from Greek classical antiquity on the island of Nisyros, Greece.

(left to right)

• Amber stone (IJmuiden, fished from the North Sea).
• Copal (two million years old, Antsiranana, Madagascar).
• Two amber stones (34 to 48 million years old, Mierzeja Wislana & Krynica Morska, Baltic Sea, Gdańsk Bay, Poland).

Amber was a precious material as described by e.g. Theophrastus of Eresus, Tacitus and Pliny the Elder.

The arsenic in arsenic bronze has cost the life of many blacksmiths.

Ever seen poisonous arsenic? Looking at it is fine (see the dark spots), touching is strongly discouraged.

Replica of a knife from the Late Bronze Age found in a grave in present-day Switzerland.