from
The Collaborative International Dictionary of English v.0.48
Spiegel iron \Spie"gel i`ron\ [G. spiegel mirror + E. iron.]
(Metal.)
A fusible white cast iron containing a large amount of carbon
(from three and a half to six per cent) and some manganese.
When the manganese reaches twenty-five per cent and upwards
it has a granular structure, and constitutes the alloy ferro
manganese, largely used in the manufacture of Bessemer steel.
Called also {specular pig iron}, {spiegel}, and
{spiegeleisen}.
[1913 Webster]