| Vendor | Spec | Unit | Price | Currency | Date |
| Qingdao Chengxin Hongfeng Chemical Co., Ltd. | China national standards | MT | 534.41 | USD | 20250922 |
| Qingdao Chengxin Hongfeng Chemical Co., Ltd. | China national standards | MT | 534.25 | USD | 20250919 |
| Qingdao Chengxin Hongfeng Chemical Co., Ltd. | China national standards | MT | 534.57 | USD | 20250918 |