Corner circles on isolated land survey plans are drawn in what ink color?

• A. Red ink
• B. Blue ink
• C. Black ink
• D. Green ink

Answer: (C)

Corner circles mark fixed reference points on an isolated land survey plan, so they need to be instantly recognizable and durable across reproductions. Black ink provides the strongest, most stable contrast on white paper and remains legible when photocopied or reduced. This makes the control points clearly identifiable in archival copies, which is essential for any future re-survey or verification. In contrast, other colors are typically used for non-permanent notes or drafting stages, such as revisions or proposed changes, so reserving black for these corner markers keeps the critical reference markers uncompromised and easy to read.