Black Ink on a Yellowing Certificate

This certificate hung around Mom and Dad's house for decades, not much spoken about. It reveals that Dad's dad, William James Woods, was a member of the Imperial Grand Black Chapter of the British Commonwealth (or just the "Royal Black Institution"). I've always found the iconography and typeface upon the certificate somewhat unsettling, but I took a photo before disposing of it. (Apologies, Dad.) 

According to the Internet, the Royal Black Institution is just a fraternal order for Orangemen; Protestant Irish folks. It seems pretty Christian-y, so not really my sort of thing, but a cursory Internet search reveals nothing particularly nefarious. It's not that I normally go about investigating fraternal orders; again, it's just that this particular physical object always gave me bad vibes. Maybe it's just the frame or the faded paper, I don't know. 

On the other hand, Google's LLM claims that certificates like this are sometimes sought after by collectors interested in secret societies, with certificates like this one going for up to $100. (No sale.) Who do I trust--Google's prone-to-hallucinations LLM or the suspiciously superficial royalblack.org?