  We present 101 and 151 GHz ALMA continuum images for 85 fields selected from
Herschel observations that have 500 micron flux densities >80 mJy and 250-500
micron colours consistent with z > 2, most of which are expected to be
gravitationally lensed or hyperluminous infrared galaxies. Approximately half
of the Herschel 500 micron sources were resolved into multiple ALMA sources,
but 11 of the 15 brightest 500 micron Herschel sources correspond to individual
ALMA sources. For the 37 fields containing either a single source with a
spectroscopic redshift or two sources with the same spectroscopic redshift, we
examined the colour temperatures and dust emissivity indices. The colour
temperatures only vary weakly with redshift and are statistically consistent
with no redshift-dependent temperature variations, which generally corresponds
to results from other samples selected in far-infrared, submillimetre, or
millimetre bands but not to results from samples selected in optical or
near-infrared bands. The dust emissivity indices, with very few exceptions, are
largely consistent with a value of 2. We also compared spectroscopic redshifts
to photometric redshifts based on spectral energy distribution templates
designed for infrared-bright high-redshift galaxies. While the templates
systematically underestimate the redshifts by ~15%, the inclusion of ALMA data
decreases the scatter in the predicted redshifts by a factor of ~2,
illustrating the potential usefulness of these millimetre data for estimating
photometric redshifts.
