PEBGLD81647 50 lbs 8-16 Mini Gold Pebble is used to repair cracks or damages that occure in pool and spa foundations. Made from a blend of cement and natural aggreagetes, pebbles are extremely durable. Using pebbles is good maintance for pool finishes, and can help prevent more expensive future repairs. Pebbles have an extremely strong bond strength, and will not shrink after installation.