  High purity TeO2 crystals are produced to be used for the search for the
neutrinoless double beta decay of 130Te. Dedicated production lines for raw
material synthesis, crystal growth and surface processing were built compliant
with radio-purity constraints specific to rare event physics experiments. High
sensitivity measurements of radio-isotope concentrations in raw materials,
reactants, consumables, ancillaries and intermediary products used for TeO2
crystals production are reported. Production and certification protocols are
presented and resulting ready-to-use TeO2 crystals are described.
