Famous 'Aspect Experiment' -- Which Type of Polarizers Were Used?

[d_bar_x]

TL;DR Summary

Which type of polarizers were used?

Does anyone know exactly which kind of polarizers were used in the famous Aspect experiment from 1982? I've read they were crystal polarizers. Does that mean Calcite, or Nicol, or something else?

[Reference link added by the Mentors:]

https://en.wikipedia.org/wiki/Aspect's_experiment

 

[pines-demon]

With the use of two-channel polarizers, we have performed an experiment following much more closely the ideal scheme of Figure 1. Our polarizers were polarizing cubes with dielectric layers transmitting one polarization and reflecting the orthogonal one.††

††A similar experiment, using calcite two channel polarizers, had been considered at the University of Catania

from https://arxiv.org/abs/quant-ph/0402001 it is a bit ambiguous, but I would guess calcite too.

Edit: Note that Nicol prisms are made of calcite too, but in Aspect's habilitation, he refers to Wollaston's prisms (unfortunately only in theoretical framework and not the experimental one). In diagrams of the experiments the polarizers look very cubical, definitely not Nicol.