Definition of "metallic"

[…] and, lo ! a palace towering ſeems, / With Parian pillars and metallic beams.

a. 1712, William King, “Rufinus: Or, The Favourite”, in The Works of the English Poets, volume XX, page 374

These chemical distinctions then, to which we have referred, are quite independent of physical condition. For instance, amongst the most metallic of the metals is a gas.

1878, Sir Norman Lockyer, “On Dissociation”, in Studies in Spectrum Analysis, page 167

No sooner had these syllables passed my lips, than—as if a shield of brass had indeed, at the moment, fallen heavily upon a floor of silver—I became aware of a distinct, hollow, metallic and clangorous, yet apparently muffled reverberation.

1839, Edgar Allan Poe, “The Fall of the House of Usher”, in Tales, London: Wiley & Putnam, published 1846, page 81

As Robert Clergerie, whose unisex Popée shoe comes in an array of pastels and eye-popping metallics, explained the attraction, “It gives manhood to women.”

2007 May 24, Karin Nelson, “Keeping Time in Cool Comfort”, in New York Times‎