This is an album that’s almost guaranteed to start arguments among genre purists. Is it metal? Is it prog? Stoner rock? Or some sort of new hybrid? The truth is, “Time in Stone,” the second full-length album from Portland band Sunrunner, is all of these things and more. By dipping into multiple musical wells and mixing and matching genres (sometimes within the space of a single song), the band creates a unique sound that can only be described as, well, Sunrunner.

Opening track “The Temple” starts as a full-on metal number, with a chugging riff and galloping tempo that gives the song an element of raw energy not unlike something written during the New Wave of British Heavy Metal. The twin leads courtesy of Frank Navarro and Doug Porter certainly call to mind vintage Iron Maiden. The layered harmonies of the chorus and the time changes during the verses, however, seem more in line with the progressive hard rock of early Uriah Heep.

“Blood Wave” is another metallic track, this time mining stoner rock territory. The album was recorded on 2-inch analog tape, which gives a nice warm feeling to the overall sound, and adds a very cool, low-slung ’70s vibe to this track. There’s also some proggy elements too, thanks to the subtle use of viola and some very Rush-like time changes.

“Gaiascope” contains what is perhaps vocalist David Joy’s best performance on the whole album. He sounds strong and confident on the verses, occasionally testing the limits of his range but never straining. This is one of two tracks on the album that clock in at over nine minutes, and it may turn off some listeners with shorter attention spans. It does get a little sluggish at times when the tempo slows way down. Then again, it certainly makes the chugging, up-tempo metal of the main riff sound that much heavier when it comes marching back to the fore.

The next two tracks are instrumentals. “Somnium” lumbers along with a satisfying Sabbath-like stomp. “Sacred Source” is the more progressive of the two, though the flute is reminiscent of “Solitude,” a melancholy Black Sabbath ballad from 1971’s “Master of Reality” album. “Sacred Source” serves as a sort of intro to “The Salamander,” one of the mellower tunes on the album. The distorted guitars are more restrained here, and the song almost flirts with jazz at one point. There are more twin leads toward the end as well, but this time they’re less Maiden and more Thin Lizzy.

“Follow the Path” is almost entirely acoustic, and there’s a sort of medieval feel to the strummed guitars. When the flute reappears, it’s hard not to think of Jethro Tull. Sunrunner may lose some of the metal heads at this point on the album, but the prog rock fans will eat this up.

And patient metal fans will be rewarded once “Hurricane Jupiter” kicks in. This is the album’s best track, with a terrific Metallica-esque riff and a magnificently hooky chorus that will have any self-respecting headbanger raising the horns in salute. The song climaxes with a trippy bit of Floydian sound collage featuring vintage astronaut radio chatter.

Album closer “Extranatural Superterrestrial” is where Sunrunner really cranks up the musical blender. Elements of prog rock and jazz slip and slide over and around one another, all atop an infectious bass line and accentuated by ethereal female backing vocals. Around the six-minute mark, the song does an abrupt about-face back into solid metal territory, this time evoking the longer, late-period Iron Maiden compositions. This is the track where Sunrunner most effectively combines metal and progressive rock, and fans of modern prog metal bands like Dream Theatre and Fates Warning will find a lot to like here.

“Time in Stone” may prove to be too heavy for the Yes/ELP crowd, and it may sound too frilly for the leather-and-spikes set. Still, there’s more than enough heft to please your average metal head, and the instrumental prowess and tricky time changes will definitely appeal to the more adventurous prog fans. This is a much more focused effort than Sunrunner’s debut album, “Eyes of the Master,” and, as the band’s sound continues to develop, “Time in Stone” may turn out to be one of those all important “cusp” albums. Fans will point to this record and say “This is where things really started to come together.” Based on the progress they’ve made so far, Sunrunner’s next album should be mind-blowing. Keep an eye on this band.

Stream the album for free at deporterrecords.bandcamp.com/album/time-in-stone, and download it for the bargain price of just $5. Be sure to keep up with all things Sunrunner at sunrunnermusic.com.

Rick Johnson is a freelance writer and radio host from Westbrook. He can be reached at:

rjohnson.rock@gmail.com