Sand Cay

Sand Cay, also known as Bailan Island and Son Ca Island, is a cay on the north edge of the Tizard Bank of the Spratly Islands in the South China Sea. With an natural area of, it is the ninth largest, and the fourth largest Vietnamese-administered, of the Spratly Islands. The island has been occupied by Vietnam since 1974. It is also claimed by China, the Philippines, Vietnam, and Taiwan.
According to reports for 2025, Vietnam expanded the island to 40 hectares with land reclaimed from the sea.

Sovereignty

The island has been occupied by Vietnam since 1974. By the later half of the 20th century, no nation had complete sovereignty on the islands.

Geography

Part of the Tizard Bank, Sand Cay lies east of Itu Aba Island, which is occupied by Taiwan. It is long, wide, and has an elevation of to at low tide. There is a high light house on the islet. Sand Cay is commonly confused with Sandy Cay which is a sandy shoal near Thitu Island.
In 2022, news reports indicated that the Vietnamese government was engaged in dredging and landfill operations to expand the size of Sand Cay, Namyit Island, and Pearson Reef. The total area of the land reclaimed in these operations was estimated to be 170 hectares.

Ecology

Sand Cay has no natural fresh water. The islet's coral sand is covered with a thin layer of fertile humus mixed with guano. The vegetation is mainly Barringtonia asiatica, Ipomoea pes-caprae, Casuarinaceae species and some grasses. In recent years, islanders have cultivated fruit trees such as pomelo, jackfruit, dragonfruit, sugar-apple and guava. Sand Cay is usually visited by seabirds, and its surrounding water is rich with fish, sea snails and sea cucumbers.