The observatory of Dunsink registered in all eleven shocks, all of the fifth grade of Mercalli’s scale, and there is no record extant of a similar seismic disturbance in our island since the earthquake of 1534, the year of the rebellion of Silken Thomas.
There are no more uses of "extant" in the book.
Show samples from other sources
But as you know, to do this with extant technology would have been prohibitively expensive for the average person.
Dave Eggers -- The Circle
"That was one of only five extant copies!" he moaned.