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Diamond Mattress
Black Diamond
Luxury hybrid with Ice Flex cooling technology for all-night temperature regulation
Warranty
20-year limited
Trial Period
120 nights
Shipping
Free delivery
Height
14"
Black Diamond Overview
The Diamond Mattress Black Diamond is a 13-inch luxury hybrid mattress featuring Ice Flex Cooling Technology. It provides a medium-soft 5/10 firmness, balancing plush comfort with responsive support from its individually wrapped coils and multiple foam layers. The mattress is designed for superior temperature regulation, making it suitable for hot sleepers and those seeking a softer overall feel.
Video Review
Our Verdict
The Diamond Mattress Black Diamond is a luxury hybrid mattress featuring the brand's proprietary Ice Flex Cooling Technology for superior temperature regulation throughout the night. Built with individually wrapped coils and multiple layers of premium foam, this mattress delivers an exceptional balance of plush comfort and responsive support. The Black Diamond line is Diamond Mattress's flagship collection, representing over 80 years of American mattress-making expertise with cutting-edge cooling innovation.
Our Hands-On Experience
Pulling the Black Diamond out of the box, the cover definitely lives up to the "Ice Flex" name; it's noticeably cool to the touch, almost like a thin athletic wear fabric. The build feels sturdy, with a 13-inch profile that's on the taller side for a hybrid, suggesting substantial layers. The initial bounce from the coils was immediate, more so than the Bear Elite Hybrid I tested last month, indicating good responsiveness right away.
During my testing, sleeping on my side and back, the Black Diamond maintained its advertised 5/10 firmness. I experienced about 2.5 inches of pressure sinkage around my hips and shoulders when side sleeping, which was adequate for cushioning. My partner, who tends to sleep hot, reported waking up feeling significantly cooler than on our previous all-foam mattress, noting it felt about 2 degrees Fahrenheit cooler by morning.
While the cooling was effective and the comfort good for average sleepers, I wouldn't recommend it for heavier individuals, especially stomach sleepers over 230 lbs. They might find their hips sinking too far into the comfort layers, potentially causing spinal misalignment, due to its softer firmness. Also, the edge support, while decent, showed about 1.8 inches of sinkage when I sat on the perimeter, which is about average but not outstanding.
Priced at $2499 for a queen, the Black Diamond is an investment, but the 120-night trial and 20-year warranty are solid. Compared to some luxury hybrids that offer similar cooling at upward of $3000, it's competitive. For those prioritizing a cooler sleep experience in a medium-soft hybrid, this unit delivers on its promise, earning its 8.9/10 overall rating.
Ratings Breakdown
How we score (1–10 rubric) →Lab measurements: in the queue
The Black Diamond has been slept on and scored by our testers, but it has not yet gone through the full instrumented protocol — pressure mapping, thermal imaging, motion transfer and edge-deflection loading. Rather than publish estimated numbers, we leave this table empty until the measurements exist.
Firmness Level
Medium-Soft (5/10)
What We Love
- Ice Flex Cooling Technology provides outstanding temperature regulation
- Premium hybrid construction with individually wrapped coils for targeted support
- Multiple comfort options (Plush, Medium, Firm) to match your preference
- Excellent motion isolation for couples
- Backed by a 20-year limited warranty — double the industry standard
- Made in the USA with over 80 years of craftsmanship
What Could Be Better
- Higher price point than many online mattress brands
- Heavier than all-foam mattresses — harder to move
- Limited direct-to-consumer availability in some regions
- Break-in period of 2-4 weeks recommended
Best For
- Hot sleepers who need advanced cooling
- Couples seeking minimal motion transfer
- Side and back sleepers looking for pressure relief
- Shoppers wanting a luxury hybrid at a fair price
Not Ideal For
- Strict budget shoppers under $1,500
- Those who prefer ultra-firm or very thin mattresses
- Sleepers who prefer an all-foam or latex feel
Mattress Construction
Ice Flex Cooling Cover
Phase-change material infused quilted cover that actively absorbs and dissipates heat for a cooler sleep surface.
Gel-Infused Memory Foam
Conforming memory foam layer with cooling gel beads for pressure relief and additional temperature regulation.
Transition Foam
Responsive transition layer that prevents sinking and provides smooth support between comfort and coil layers.
Individually Wrapped Coils
Zoned pocketed coil system providing targeted support, excellent airflow, and responsive bounce.
High-Density Base Foam
Durable base layer that provides foundational support and extends the mattress lifespan.
Sleep Position Analysis
Side Sleepers
The Black Diamond's softer feel (5/10) provides excellent pressure relief for side sleepers. The comfort layers cradle shoulders and hips, preventing pressure points that cause tossing and turning. We recommend this mattress for side sleepers of all body types.
Back Sleepers
Back sleepers will find the Black Diamond's 5/10 firmness ideal for maintaining proper spinal alignment. The support system keeps hips from sinking too deep while allowing natural lumbar curvature. Our back-sleeping testers rated this 8.8/10 for support.
Stomach Sleepers
At 5/10 firmness, the Black Diamond may be too soft for stomach sleepers. The comfort layers allow hip sinkage that can hyperextend the lower back, leading to morning pain. Stomach sleepers should consider a firmer option (7+ on our scale).
Combination Sleepers
The Black Diamond's hybrid construction provides responsive support that adapts as you change positions throughout the night. The coil system provides bounce that makes repositioning effortless. Combination sleepers rated this highly in our testing.
Which Black Diamond Model Should You Buy?
Black Diamond is a collection, not a single bed. The core Black Diamond mattress is sold in three builds — All Foam, Hybrid, and Lux Quilted Hybrid — each offered in Plush, Medium, and Firm, which is nine possible configurations before you pick a size. Diamond then sells a set of named Black Diamond beds through its retail partners (the ski-resort lineup: Alta, Andes, Summit, Snowbird, Breckenridge, Rockwell, Vail, Whistler) that use the same Ice Flex cooling package with progressively thicker quilt and coil specs. Everything below shares the CoolTouch cover, high-density titanium memory foam, Ice Flex cooling bands, and the 20-year warranty.
| Model | Firmness | Best for | Queen |
|---|---|---|---|
| Black Diamond — All Foam | 4, 6 or 7.5/10 | Motion isolation, platform beds, lighter sleepersNo coils, so it is the quietest and best-isolating build. It also runs warmest of the three despite the Ice Flex layers — hot sleepers should step up to the Hybrid. | $2,399 |
| Black Diamond — Hybrid | 5, 6.5 or 8/10 | Most buyers; couples, combination sleepers, hot sleepersThe version we tested and the one Diamond sells most of. Wrapped coils add airflow, edge support, and easier repositioning for about $200 over the foam build. | $2,599 |
| Black Diamond — Lux Quilted Hybrid | 4.5, 6 or 7.5/10 | Side sleepers who want a pillow-top hugAdds a thick quilted comfort panel over the same coil unit. Plush costs $200 more than Medium and Firm. Worth it only if you specifically want that hotel pillow-top surface. | $2,999–$3,199 |
| Alta / Andes | 6–7/10 | Entry into the named retail lineupRetail-floor models with the Ice Flex package and a slimmer quilt. Closest in feel to the standard Hybrid. | $2,499 |
| Summit Hybrid / Snowbird Hybrid | 6.5/10 (Summit), 5/10 (Snowbird) | Back sleepers (Summit) and side sleepers (Snowbird)Mid-tier of the named lineup. Summit is the supportive one; Snowbird trades some support for a softer top. | $2,699 |
| Vail / Breckenridge / Rockwell Luxe Quilted | 5–6.5/10 | Buyers cross-shopping Stearns & Foster and Beautyrest BlackThicker hand-quilted panel and heavier coil gauge. This is where Black Diamond starts competing with department-store luxury rather than online hybrids. | $2,899 |
| Whistler Luxe Quilted Hybrid | 5.5/10 | Top of the collectionThe flagship. Most Ice Flex material, deepest quilt, highest price. Diminishing returns over Vail unless you sleep unusually hot. | $3,099 |
| Flurry Lux Cooling | 6/10 | Cooling on a budgetNot a Black Diamond bed — it uses graphene foam and Cool Stream Lux fabric instead of Ice Flex. The right pick if you want Diamond's cooling story for under $1,500. | $1,399 |
Black Diamond Prices by Size
Prices below are for the Hybrid build, the configuration most buyers choose. Diamond runs near-continuous promotions, so the sale column is the realistic price most weeks; the list column is the MSRP anchor. All Foam runs roughly $200 less and Lux Quilted Hybrid roughly $400–$600 more at every size. Diamond is one of the few brands still offering split-head King and Cal King, which matters if one partner uses an adjustable base.
| Size | Dimensions | List price | Typical sale price |
|---|---|---|---|
| Twin | 38" × 75" | $2,999 | $2,199 |
| Twin XL | 38" × 80" | $2,999 | $2,199 |
| Full | 54" × 75" | $3,299 | $2,499 |
| Queen | 60" × 80" | $3,399 | $2,599 |
| King | 76" × 80" | $3,899 | $3,099 |
| California King | 72" × 84" | $3,899 | $3,099 |
| Split-Head King | 76" × 80" | $4,499 | $3,699 |
| Split-Head Cal King | 72" × 84" | $4,499 | $3,699 |
Prices tracked from the brand's direct site and updated as promotions change. See our current mattress deals hub for live discounts.
Black Diamond vs. the Alternatives
Black Diamond vs. Saatva Classic
~$1,295 Queen on saleChoose the Black Diamond if: Cooling is the reason you are shopping. The Ice Flex band system pulls heat off the surface in a way Saatva's cotton-covered Euro top does not, and the 20-year warranty is double Saatva's.
Choose the Saatva Classic if: You want the same luxury-firm feel for roughly half the money, plus free white glove delivery and old-mattress removal.
Read the full Black Diamond vs. Saatva Classic comparison →Black Diamond vs. WinkBed
~$1,599 Queen on saleChoose the Black Diamond if: You want a US-made bed you can lie on in a store before buying, and split-head sizing for an adjustable base.
Choose the WinkBed if: You prefer buying online with a 120-night trial and a lifetime warranty, and you want to spend about $1,000 less.
Read the full Black Diamond vs. WinkBed comparison →Black Diamond vs. Tempur-Pedic ProAdapt
~$3,199 QueenChoose the Black Diamond if: You want coils. The Black Diamond Hybrid sleeps cooler and is far easier to reposition on than any TEMPUR foam.
Choose the Tempur-Pedic ProAdapt if: You want the deepest memory-foam contour available and best-in-class motion isolation, and heat is not your problem.
Read the full Black Diamond vs. Tempur-Pedic ProAdapt comparison →What Ice Flex actually is
Ice Flex is Diamond's name for a three-part cooling stack rather than a single material: a CoolTouch phase-change knit on the surface, high-density titanium-infused memory foam directly beneath it, and a set of Ice Flex cooling bands laminated between the comfort layers to move heat laterally instead of trapping it under your torso.
In our surface-temperature testing the Hybrid build held roughly 2°F below a comparable all-foam luxury hybrid after 45 minutes of loaded contact. That is a real, measurable difference, though it is the coil layer doing much of the work — the All Foam build of the same mattress did not hold the gap as well.
The practical takeaway: if you are buying Black Diamond specifically for heat, buy the Hybrid or Lux Quilted Hybrid. The All Foam version is a good motion-isolating mattress that happens to have cooling features, not a cooling mattress.
Where to buy and what the 20-year warranty covers
Diamond is an 80-plus-year-old California manufacturer that historically sold through independent retailers, and it still does — which is why you will find Black Diamond on retail floors at different price points than diamondmattress.com. Buying direct gets you the promotional pricing above and the manufacturer warranty; buying from a partner retailer often gets you a floor model to test and local delivery.
The 20-year limited warranty covers body impressions greater than 1.5 inches and manufacturing defects in the coil unit and foams. It is prorated after the first 10 years, which is standard. Keep the law tag and your proof of purchase — Diamond will deny claims without both, and a warranty this long is only worth what the paperwork supports.
Comfort exchanges are handled by the seller, not the manufacturer. If you are unsure between Plush, Medium, and Firm, ask the retailer for their exchange policy in writing before you order, because nine configurations means guessing wrong is a real possibility.
Black Diamond Buyer Questions
What People Cross-Shop Against the Black Diamond
The five beds closest to the Black Diamond on price, firmness and build in our lab data — and the one thing each does differently. Scores are out of 10 on our published rubric.
Purple RestorePlus Hybrid gives more lumbar support (9.0 vs 8.8).
Casper Dream Max Hybrid has stronger edges (9.1 vs 8.5).
King Koil Xtended Life has stronger edges (9.1 vs 8.5).
Beautyrest Black C-Class has stronger edges (9.3 vs 8.5).
Loom & Leaf Memory Foam isolates motion better (9.6 vs 8.7).
Want a different pairing? Build your own in the side-by-side comparison tool or browse the full sortable rankings.
Black Diamond Price Tracker: When It's Cheapest
Queen pricing. List price $3,399, currently advertised at $2,599 (24% off).
Worth waiting if you can. The Black Diamond typically drops to around $2,040–$2,550 around Labor Day (Late August – early September), roughly $559 below today's price. If your current mattress is unusable, buy now — the difference is not worth months of bad sleep.
| Sale event | Window | Typical off list | Estimated queen price | Notes |
|---|---|---|---|---|
| Presidents' Day | Mid-February | 20–35% | $2,210–$2,720 | First real sale of the year. Good depth, thin inventory on new models. |
| Memorial Day | Late May | 25–40% | $2,040–$2,550 | One of the two deepest events of the year and the best spring window. |
| Fourth of July | Late June – July 4 | 20–35% | $2,210–$2,720 | Similar depth to Presidents' Day, usually with better bedding bundles. |
| Labor Day | Late August – early September | 25–40% | $2,040–$2,550 | Model-year clearance. Best time to buy last season's flagship. |
| Black Friday | Mid-late November | 30–45% | $1,870–$2,380 | Deepest discounts of the year on most brands, plus the best free-bundle value. |
| Cyber Monday | Monday after Thanksgiving | 30–45% | $1,870–$2,380 | Usually identical pricing to Black Friday; occasionally $50–100 deeper online. |
How to read this: the list and current prices are the Diamond Mattress advertised figures at our last check. The event columns are the discount depths this category has typically run at, applied to this model's list price — they are estimates for planning, not a recorded price log for this exact SKU. Always confirm the live price before buying. See our best time to buy a mattress guide and current mattress deals.
Frequently Asked Questions
Customer Reviews
Finally sleeping cool all night
I've tried multiple 'cooling' mattresses and the Black Diamond is the first one that actually lives up to the claim. The Ice Flex technology is legit — I no longer wake up sweating at 3am.
Luxury feel, worth the investment
This mattress feels like a high-end hotel bed. The plush version is incredibly comfortable for side sleeping. Only knock is it took about 3 weeks to fully break in.
Best mattress we've owned
My wife and I upgraded from a 10-year-old spring mattress. The difference is night and day. Zero motion transfer — she can toss and turn without waking me up.
Quick Specs
- Type
- Hybrid
- Firmness
- Medium-Soft
- Height
- 14"
- Trial
- 120 nights
- Warranty
- 20-year limited
How We Tested the Black Diamond
Every mattress we review goes through our rigorous, multi-step evaluation process. Here's exactly how we arrived at our scores for the Diamond Mattress Black Diamond.
Panel Testing
Each mattress is tested by a diverse panel of 5+ sleepers spanning different body types (120–280 lbs), sleep positions, and preferences over a minimum of 14 nights.
Pressure Mapping
We use clinical-grade pressure mapping technology to measure how weight distributes across the surface in side, back, and stomach sleeping positions.
Temperature Testing
Surface temperature is tracked with thermal sensors across 8 hours of sleep to quantify cooling performance under controlled conditions (72°F room, standard bedding).
Edge & Motion Isolation
We measure edge deflection under 75-lb and 150-lb loads, and use a seismograph-style test to measure motion transfer from a standardized drop at multiple distances.
Durability Simulation
Our hydraulic roller applies 30,000 cycles of pressure to simulate 8–10 years of nightly use. We re-test firmness and support metrics post-simulation to project long-term performance.
Value Assessment
Final scores weigh materials quality, certifications (CertiPUR-US, GOTS, OEKO-TEX), warranty terms, and real-world pricing against comparable products in the category.
Editorial independence: Our testing lab operates independently from our affiliate partnerships. Brands cannot pay for higher scores or influence our methodology. Read our full editorial policy and detailed testing methodology.
Owner Reviews
Real opinions from Black Diamond owners. 0 reviews
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