No need to be embarrassed. I bet there's a few people around here concealing secrets like that.
As a kid I used to climb sandstone cliffs (Wollongong NSW) about 150 feet high with no rope at all.
Of course, that was before before I "graduated" to using my mate's rope which I suppose was either nylon or polypropylene. It was hawser laid with no mantle and slippery as pigshit and had more bounce than a rubber band. About 10mm diameter.