"small pebbles" is correct and usable in written English.
For example, you could use it in a sentence like "The ground was littered with small pebbles."
Grit, sedimentary rock that consists of angular sand-sized grains and small pebbles.
They symbolize the sixteen small pebbles the couple will face during their marriage.
They will rest over it like small pebbles inside a timer designed for fine grains of sand.
If you look closely, you'll notice there are sixteen small pebbles placed in various locations throughout the church.
Small pebbles and sand gently shelve into a crystal clear bay – lots of fish to spot if you go snorkelling.
Put the pot on a wide saucer filled with small pebbles, kept wet but not covered with water.
Mechanical properties such as compressive strength are necessary for the design of fusion blanket packing the small pebbles.
Starting in the late 1980s and 1990s, explorers and nomads discovered that dark-colored meteorites stood out against flat, featureless areas covered by sand and small pebbles.
Shaped like Russian nesting dolls, Schärer's Madonnas have masklike slits for eyes and, in some cases, broad grimaces made up of small pebbles.
Porth Llanlleiana, the most northerly beach in Wales, is a perfectly formed cove of small pebbles, which are comfortable underfoot and smooth enough for sunbathing.
"All my reporting life, I have thrown small pebbles into a very large pond, and have no way of knowing whether any pebble caused the slightest ripple.
