What is the minimum diameter for cylindrical corner monuments?

• A. 10 cm
• B. 12 cm
• C. 15 cm
• D. 20 cm

Answer: (C)

Stability and durability drive the choice here. A cylindrical corner monument needs enough cross‑section to resist tilting, shifting, and damage once buried in a concrete base. A 15 cm diameter gives a practical balance: it’s large enough to provide solid resistance in the ground and still be easy to handle, install, and mark or read later. Smaller diameters, like 10 or 12 cm, are more prone to tipping or cracking under field stresses and are harder to badge with durable inscriptions. A 20 cm diameter would work, but it isn’t necessary to meet minimum stability and would add unnecessary cost and bulk. So 15 cm is the standard minimum that safely covers the main needs of a cylindrical corner monument.