The people behind Los Angeles’ highly acclaimed Thunderbolt bar have officially opened Semiprecious in Denver’s Sunnyside neighborhood. But the bright bar isn’t just a carbon copy of its LA sister, it’s completely built for the Mile High.
“It’s a totally different concept,” said owner Mike Capoferri, who’s Thunderbolt is known for its tech-forward approach to making cocktails paired with a southern hospitality vibe, think fried chicken buttermilk biscuits and collard greens. Semiprecious, he continued, “is sort of a melange of Western European aperitivo cultures,” and takes inspiration from Italy, Spain, France, and Portugal.
To create the all day happy hour ambiance, the team has really leaned into the bar’s southwest-facing patio, which gets sun all day long.

“That’s been one of the beautiful things. Typically, at a bar the hardest hours to fill are those early hours, but that’s when we’ve been slammed so far,” said Capoferri. “Everyone wants to come do aperitivo [with] daytime vibes.”
From LA to Sunnyside in Denver
Capoferri also owns Night on Earth in LA, and the choice to open his third bar in Denver wasn’t random, he has a long history with the Mile High City. He made several trips to the city during his years as Campari’s Italian portfolio ambassador, where Denver was a focus market of his. It was during that time he met Jon Hartman, owner and founder of the Denver-based design studio, Wunder Werks.
Hartman helped Capoferri with the brand identity and interiors for Thunderbolt and Night on Earth, so when he approached Capoferri with the opportunity to open a new concept in Sunnyside it felt like a natural fit.
“Jon, Wunder Werks, and a development group called Natural Object purchased the building we’re in…and they did a ton of research into areas they thought could use a little commercial and retail stimulus, which is why they chose that site,” Capoferri explained. “I think it was a brilliant move to go into a place like Sunnyside where so many people are moving in so much of the demographic there is exactly the kind that wants a cocktail bar like Semiprecious.”

The opening appears to be a good call, there are no other bars within walking distance of Semiprecious, despite the area’s growing population.
Locals have shown up in full force, and the Denver hospitality community has been nothing but supportive.
“You never know when you’re new in town, sometimes it’s weird or competitive, but Denver has been the opposite,” he added. “It’s really felt like a community effort.”
Building a Bright and Beautiful Bar
It’s clear that the team thoughtfully designed the space specifically to exist on that sunny corner at West 44th Street and Elm Court. Drawing inspiration from a mid-century workshop, the space mixes sleek lines, natural materials, and deep red tones to create an atmosphere that’s approachable yet design-forward.
“We knew we wanted it to be beautiful, but not too fancy, casual, but not too precious,” said Capoferri. “It’s honestly been our strongest opening out of the three bars we own.”
Engineered Cocktails For Perfection
At Semiprecious, drinks aren’t simply shaken or stirred, they’re engineered. The bar employs the same high-tech cocktail techniques that made Thunderbolt famous, reimagined through an aperitivo lens.

At the heart of Semiprecious’s approach is a belief that cocktails should be served at their optimal temperature, right at or just above freezing. To achieve this, the bar builds each drink around a higher alcohol content, which lowers the freezing point. This allows them to batch and refrigerate fully diluted cocktails without relying on ice, so each pour is perfectly cold and precisely balanced.
“That’s why we’re able to serve a perfect martini,” explained Capoferri. “We get it to the exact right dilution and temperature and serve it instantly. A martini should be absolutely arctic cold, every sip.”
Much of Semiprecious’s magic lies behind the scenes in a suite of high-tech systems. That includes a custom refrigeration set to keep the booze at the ideal temp. Sparkling drinks are force-carbonated in-house using high-pressure techniques and served from sealed bottles to preserve every bubble. The bar also implements methods that allow dilution without the use of ice. For example, the Porcini Vieux Carré, where dilution comes from mushroom dashi (the savory broth left behind after rehydrating porcini mushrooms). That umami-rich liquid replaces water, adding depth while preserving precision chilling.

“It’s all designed to eliminate anything superfluous from the modern cocktail experience,” Capoferri notes.
Other cocktails include house-carbonated highballs and spritzes that capture a golden-hour vibe, alongside citrusy shaken cocktails, spirit-forward sippers, and reimagined classics. Ingredients like French cognac, Spanish vermouth, and Italian amaro reinforce the aperitivo theme, even in agave- and whiskey-based drinks.
On the food side, there are elevated snacks crafted to complement the drinks, not compete with them. The bar teamed up with So Damn Gouda a few blocks away to offer a rotating selection of small plates like meats, cheeses, dolma, olives, and more.
While the technology is cool (pun intended), what’s more important to Capoferri is that drinks come out fast, consistent, affordable, and delicious.

“We’re not trying to create a bar that’s all about theater or showing off technique,” he said. “Everything is designed to happen quietly in the background.”
More To Come
While Semiprecious settles into its groove, Capoferri is experimenting with future programming. With a cabaret license in place, late-night DJs could join the weekend mix soon. Other ideas, like trivia or pop-ups, may follow, but for now, it’s about pacing and listening to what the neighborhood wants.
In the meantime, he’s just grateful. “The neighborhood has been incredible,” he says. “People were supporting us before we even opened. It’s been such a pleasure to do business in Denver.”
Visit Semiprecious Tuesday through Sunday from 4 p.m. to midnight, and Friday and Saturday from 4 p.m. to 2 a.m. 2839 W. 44th Ave., Denver, semipreciousdenver.com