  Quantum coherence plays a fundamental and operational role in different areas
of physics. A resource theory has been developed to characterize the coherence
of distinguishable particles systems. Here we show that indistinguishability of
identical particles is a source of coherence, even when they are independently
prepared. In particular, under spatially local operations, states that are
incoherent for distinguishable particles, can be coherent for indistinguishable
particles under the same procedure. We present a phase discrimination protocol,
in which we demonstrate the operational advantage of using two
indistinguishable particles rather than distinguishable ones. The coherence due
to the quantum indistinguishability significantly reduces the error probability
of guessing the phase using the most general measurements.
