The Black Diamond Library is helping blaze a trail for mail-in voting minus the stamp.

For the primary election this month, King County is trying seven, 24-hour ballot drop boxes at six branches of the King County Library System throughout the county. Black Diamond is one of them. Instead of mailing their ballots back, absentee voters can deposit them any time of the day until 8 p.m. Aug. 19, which is election day.

In addition to the Black Diamond location (24707 Roberts Dr.), the drop boxes are at the Bellevue, Des Moines, Fall City, Lake Forest Park and Algona-Pacific libraries. A seventh box is in downtown Seattle at the King County Administration Building. More information is available at http://www.kingcounty.gov/elections/voting/ballotdropboxes.aspx.

The boxes will be used for the general election in November, too, in a pilot program for which locations “were chosen on the basis of population density and geographic dispersion,” said Megan Coppersmith, a spokeswoman for the county’s elections department. Next year, the box locations will be increased to 39, including the Maple Valley and Covington libraries.

The elections department mailed more than 660,000 absentee ballots Aug. 1. Voters who requested one should have received it at their registered mailing address by yesterday. If not, election officials can be contacted at (206) 296-8683 or at http://www.kingcounty.gov/vote.

In-person accessible voting is available for all voters starting through Aug. 18 at the county elections office in Renton weekdays from 8:30 a.m. to 4:30 p.m. On election day, the hours will be 7 a.m. to 8 p.m.