How do artists use acid-etching to create gradients in concrete abstract surfaces?

Artists employ acid-etching as a transformative technique to craft gradients on concrete abstract surfaces, merging science and artistry. The process begins with applying acidic solutions—like hydrochloric or phosphoric acid—to the concrete surface, which reacts chemically to dissolve portions of the material. By controlling the acid's concentration, exposure time, and application method (brushing, spraying, or masking), artists achieve gradual tonal shifts, from deep recesses to subtle highlights.

Layering is key: diluted acid creates softer gradients, while repeated applications intensify contrasts. Some artists combine acid-etching with stains or dyes to enhance color transitions. The result is a tactile, organic texture that mimics natural erosion or celestial patterns, often seen in contemporary sculptures and architectural installations. This method bridges unpredictability and precision, allowing concrete—a rigid medium—to express fluid, ethereal beauty.