Which shells did Warspite use against the Zara class?

Which shells did Warspite and the other battleships use against the Zara-class cruisers?

The exchange does not settle the identification: armor-piercing is doubted, and the alternative type and mark remain uncertain.

A question about Warspite and the Italian Zara-class cruisers interrupts the broader ammunition comparison. Armor-piercing ammunition is doubted, but the alternative is recalled uncertainly. The precise shell mark is also left between two possibilities. This brief exchange does not establish a definitive ammunition identification.