Are LOC records common?

No. They are rarely used and never required.

Is the location verified?

No. It is whatever the zone owner published.

LOC Record

A LOC record publishes the latitude, longitude, and altitude of a DNS name, as defined in RFC 1876. This lookup shows any LOC records on a name in readable form.

When to use this: You are checking whether a domain publishes location data, or debugging a zone that uses LOC records. Command prefix loc:

About the LOC Record

Look up LOC records (RFC 1876), which publish a latitude, longitude and altitude for a name.

FAQ

Are LOC records common?: No. They are rarely used and never required.
Is the location verified?: No. It is whatever the zone owner published.