A black nanopowder composed of zinc in nanoparticles.
Zinc nanopowder is one of several nanoparticle materials being investigated for its potential as an additive in self-compacting concrete and related products. Early research shows positive results on the flexural strength of the final product.
"A black nanopowder composed of zinc in nanoparticles ranging from 40 to 100nm" -Retrieved 3/12/2021 from https://www.ssnano.com/inc/sdetail/zinc_nanoparticles__nanopowder___zn__99_7__40_60nm_/271
available online (see "9920XH Zinc (Zn) Nanoparticles/Nanopowder MSDS for Download")