Possible unlisted benchmark in Stockbridge, MA

[+CelloFellow]

I was on vacation geocaching while visiting Berkshire Botanical Garden. After finding GC8J3VA, I noticed what I thought was a benchmark nearby the geocache. I don't fully remember where exactly it was, but I'd say it was about 50ft away NW from GC along Stockbridge Rd and outside the wooden fence. I was going to log it in, but I couldn't find it on the database.

 

I did some research and I found this: https://www.primacode.com/services_surveying.htm. I believe this is the website for the company that installed the survey. I couldn't find a way to search for benchmarks on the website. I'm no expert in benchmarks at all and was wondering if someone can help me identify what this is because it got me curious.

[Bill93]

It is possible it is a bench mark not submitted to NGS, but much more likely that it is not and is a property corner set by that company. 

Most property corners in the US are simply a pipe or rebar, often with a plastic cap identifying the surveyor or their company, but in some areas and for some clients a metal cap my be more common. I would have expected a license number, though.

[Z15]

Probably related to some local project or property boundary.