Make Smoked Salmon Pinwheels quickly for elegant appetizers; assemble, chill, and slice to serve.
Lay a large sheet of plastic wrap on the white quartzite tabletop and smooth it flat. Arrange the thinly sliced cold smoked salmon in a single overlapping layer to form a neat rectangle roughly 6 inches wide by 12 inches long, longest side toward you; press each slice gently so the salmon surface is glossy and continuous, with fine ridges of flesh visible where slices overlap.
Spoon the cream cheese into a small matte grey ceramic bowl and use a butter knife or small offset spatula to spread a thin, even layer over the salmon rectangle. Work with a light touch so the cream cheese lies smooth and creamy without dislodging the salmon — you want a velvety white sheet that contrasts with the salmon’s deep orange sheen.
Cut the 1/4 medium cucumber into tidy matchsticks and lay them in a single line about 1/2 inch from the near edge of the salmon rectangle. Keep the finely chopped red onion and drained capers in two small bowls nearby, and set thin lemon slices on a small dish — everything calm and in place so the roll can be formed cleanly.
Using the plastic wrap as a guide, lift the near long edge and roll the salmon tightly around the cucumber sticks, producing a compact, cylindrical log with a smooth salmon exterior and a creamy white spiral interior. Twist the plastic wrap ends to seal and refrigerate on the quartzite until firm, at least 30 minutes, so the roll holds its shape and the textures set.

Unwrap the chilled roll and, using a very sharp knife, slice straight down to produce sixteen glossy 1/2-inch-thick pinwheels. Wipe the blade between cuts to keep clean spirals; each slice should reveal a tight spiral of cream cheese and cucumber against the translucent salmon.
Arrange the pinwheels neatly on a shallow white ceramic plate, sprinkle the finely chopped red onion and capers over the top, and tuck thin lemon slices at the edge for brightness. The finished plate should show glossy salmon spirals, creamy white interiors flecked with green cucumber and purple onion, tiny glossy capers, and a restrained, elegant composition for serving.
