The 石切場 consists of a large area with a wide selection of rocks and ore deposits that are randomly generated upon creation, and will continue to generate new deposits each day.
You will gain access to the Quarry upon completion of the クラフトルーム in the 公民館 which rewards you with the Bridge Repair. The bridge is located east of 鉱山 and the 冒険者ギルド. If the Community Center was sold to the Joja Corporation and turned into the Joja Warehouse you will instead acquire the Bridge Repair and subsequent access to the Quarry once all Crafts Room バンドル have been purchased from the Joja Community Development Form for 25,000g.
Each day a selection of new items will spawn, so to prevent valuable spawns from being blocked by existing rocks, make sure to keep the quarry entirely cleared.