The phrase "a swatch of a" is correct and usable in written English.
It can be used when referring to a sample or piece of material, often in the context of fabric or color selection.
Example: "She brought a swatch of a vibrant blue fabric to show her design idea."
Alternatives: "a sample of a" or "a piece of a".
Nearby was a swatch of a fisherman's knit.
One woman — a book open on her lap, a swatch of a purple sweater waving out over washed-out jeans, her face perhaps pointedly outside the frame — says only this to her would-be inquisitor: "These experiences were so meaningful to me that I don't want you to soundbite them".
His pigeonholed "Art Reliquarium," one of many such pieces he has made, holds, among other things, a swatch of a St. Marks Baths bathrobe, circa 1971; funerary ashes; and a coil of the red ribbon used to make the first batch of AIDS lapel insignia in 1991.
One woman a book open on her lap, a swatch of a purple sweater waving out over washed-out jeans, her face perhaps pointedly outside the frame says only this to her would-be inquisitor: "These experiences were so meaningful to me that I don't want you to soundbite them".
If you're using an already-established knitting pattern, it will tell you how many stitches and rows it should take you to make a swatch of a certain size.
He did the same with a swatch of vinyl, a piece of fine stationery, and a square of rough plastic.
On one side is a swatch of sienna, like an abstract wave.
Over time, the pebbles grow a swatch of ice on their tops, like a bad toupee.
Laura held up a swatch of cream jersey with a raised, wavy texture that suggested sand dunes.
On an earlier trip, Mr. Green had selected a swatch of clothing for a custom-made suit.
She has a magpie eye for minutiae: the crosshatching in a swatch of silk; the latticework on a Nigerian shirt.
