Leonard Kniazeff is an ACTIVE stratovolcano in Compostela Valley on the island of Mindanao. The date of the last eruption is dated at around 120AD.
Philippine Lakes #xxx, 5 Nov 2018
part of a Souvenir Sheet of 2
The right-hand stamp shows Leonard Lake which is crater lake, approximately 1.8 x 0.8km wide, located in Leonard Kniaseff.
Thailand 2018 World Stamp Exhibition
featuring Philippine Lakes Souvenir Sheet with Additional Imprint #xxx, 28 Nov 2018
part of a Souvenir Sheet of 2 (se-tenant block) with special embelishments of silver hot foil stamping and die cut