In reply to Alex Edge:
As far as pro is concerned there are two options.
For sea cliff climbing (softer chalk at the bottom due the capillary action of the salt water, to harder in the middle and choss at the top, it’s generally warthogs banged in on the lead while hanging off or clipped into your tools, to an equalised lower off just under the choss ar the top, or topping out for the brave / mad.
You then pull the ropes and lead it clean - a form of sport chalk pioneered by Dave Pegler and others.
For inland / quarried chalk, I have used 30 cm long 12 mm A4 threaded stainless steel bar glued in with a s/steel hanger, s/steel washer and nylock nut. Then static rope bridles at the top for lower offs. Again a type of sports chalk.
Neither are cheap! But good fun and good training for ice.