Air Abrasive Jet Machining (AJM) is used to machine thin ductile and brittle sections, yet conventional abrasives (aluminium oxide, silicon carbide, and garnet) are mined resources with a significant environmental footprint. This study assesses sieved, washed beach sands from local Goan beaches as sustainable abrasives for AJM of 2 mm mild steel. The AJM rig was used, and five factors - air pressure (P), nozzle diameter (d_N), stand-off distance (S), abrasive flow rate (A), and impingement time (T) - were varied using a Taguchi L₂₇ design. Material Removal Rate (MRR) and Kerf Taper Angle (KTA) were measured and optimized via the Mixed Aggregation by Comprehensive Normalization Technique (MACONT). d_N influenced MRR, whereas S dominated KTA. Benaulim sand (≈ #60) produced higher MRR but larger KTA, and Agonda sand (≈ #40), yielded lower MRR but smaller KTA. Optimal settings for Benaulim sand were 8 bar P, 2.5 mm d_N, 2 mm S, 470 g/min A and 600 s T, yielding MRR ≈ 0.00077 g/s and KTA ≈ 3.15° and for Agonda sand, 8 bar P, a 3 mm d_N, 2 mm S, 370 g/min A, and 540 s T, gave MRR ≈ 0.00043 g/s and KTA ≈ 0.28°. Compared with garnet (≈ #80) in Abrasive Water Jet Machining (AWJM), these beach sands have reduced MRR but delivered improved KTA, demonstrating their promise as low-cost, eco-friendly AJM abrasives.