Stephen Petronio Company returns to The Joyce with the world premiere of Hardness 10. Titled in reference to the diamond as the hardest gem, Petronio’s third collaboration with composer Nico Muhly arcs from amorphous rumblings to glimmering clarity. The fourth installment of the company’s Bloodlines project, a series of revivals of works by titans of postmodern dance, continues with Merce Cunningham’s playful and indeterminate Signals (1970), performed with live music from Composers Inside Electronics. Also on the program is an excerpt from Petronio’s darkly abstract Underland (2003), inspired by the music of Australian legend, Nick Cave.