I just posted about this recent incident on the Canyoning Australia forum (https://canyoning.org.au/forum/viewtopic.php?f=14&t=284), but figured it was also relevant to US canyoneers. The incident occurred in a sandstone slot canyon in the Blue Mountains that is reasonably well known, but not particularly popular due to its remoteness. There are probably only a few dozen groups that visit it each year. It is popular enough to have fixed anchors (natural anchors with slings and maillons). The group that had this near miss were all experienced canyoners. The first person in the group checked the anchor and rigged the rope. They said the screw gate was lose but was then tightly closed by hand. The triangular maillon didn’t appear to be misshaped. They descended without incident. The next member of the party then descended. They also noticed nothing wrong with the maillon before setting off. They were not heavy and did not do anything unusual or shock load the anchor while descending. As shown in the photo below, the maillon failed catastrophically during this descent. Thankfully the rope caught on the bent arm until the abseiler reached the ground. Had the rope not caught, the person would have suffered a serious fall. The information I have is that the maillon that failed was a Maillon Rapide brand, zinc plated steel Delta (triangular) maillon. The stamped rating confirmed it was 6mm diametre and had a Working Load Limit (WLL) of 250kgs. This is a good brand, rather than a hardware store knock-off, and is a reasonable diametre (I've certainly found much smaller maillons in canyons). Given that the maillon that failed was a recognised brand, a reasonable diametre, and being used well within its safe working load, this incident is particularly concerning. It highlights how easily a core component of an abseiling anchor can fail, with potentially catastrophic consequences. I've outlined the lessons I took from it here: https://canyoning.org.au/forum/viewtopic.php?f=14&t=284 I'd really appreciate any additional thoughts / lessons regarding this incident.