Kalkrav was a planet.
By the time Bernice Summerfield visited Danpetro at an early point in her life, Kalkrav's nomadic culture had been studied by an archaeologist named Wilby. (PROSE: A Game of Soldiers)
In 2582, Adjudicator forces fought against the Kalkravian Revolution.
In 2592, three Kalkravian nuns were observed at a transmat station on a human colony planet while Chris Cwej and Nyssa were there. (PROSE: Cold Fusion)
In the 2600s, Anderson's ship had seats with hand-stitched Kalkravian leather. (PROSE: The Big Hunt)
Following the Battle of Capra in the Deindum War, Irving Braxiatel imported Kalkravian Marble to Capra and had it carved into the Capra Marbles. (PROSE: Winging It)
In the 46th century, a tomb for Bernice Summerfield existed in the Kalkravian asteroid belt. (PROSE: Paydirt)
In the era of the Twelve Galaxies, Kalkravian firewine was served at Miranda Dawkins' imperial reception at the Needle. (COMIC: Miranda)
Behind the scenes
Kalkravians have only been mentioned in stories written by Lance Parkin.
Non-valid material
During the Last Great Time War, Time Lords tricked Kalkravian arm dealers into fighting for them by opening a space warp between the Kalkravian home systems and a nameless planet half a million years in their past which had been invaded by Daleks. As a result the War Doctor found traces of Kalkravian words on that planet, including plak-than-qa – "armed insurgency with disruption of industrial processes". (NC: Climbing the Mountain)