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Diamond Mattress
Black Diamond
Luxury hybrid with Ice Flex cooling technology for all-night temperature regulation
We publish a number only when it is backed by our physical protocol. This review is a research evaluation of published specifications and policies.
312 customer reviews on DiamondMattress's website
Queen price on record
Warranty
20-year limited
Trial Period
120 nights
Shipping
Free delivery
Height
14"
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.
Black Diamond Photos
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.
Firsthand mattress experience
Ben Trapskin has personally evaluated this model in person through his mattress retail work. Ben also owns Yawnder, a mattress retailer. These personal observations are distinct from Sleep Sage's research assessments and instrumented laboratory tests. In-person familiarity does not establish overnight home testing or measured performance results.
Sleep Sage may earn commissions from qualifying purchases. Disclosure · Our methodology
Video Review
What Our Research Found
This assessment is based on published manufacturer specifications, materials analysis and verified owner feedback. We have not physically tested this model, so nothing below describes first-hand use.
The build feels sturdy, with a 13-inch profile that's on the taller side for a hybrid, suggesting substantial layers.
They might find their hips sinking too far into the comfort layers, potentially causing spinal misalignment, due to its softer firmness.
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.
Performance assessment
How we score (1–10 rubric) →Evaluated through published specifications, manufacturer information and materials analysis. Not physically tested in our lab. We do not publish cooling, motion-isolation, edge-support, pressure-relief, response, durability or off-gassing scores for the Black Diamond until the full protocol is complete. Everything below — construction, materials, firmness, pricing, trial and warranty — is verified specification and editorial analysis.
Research evaluation — full lab score pending
The Black Diamond has been evaluated from published specifications, manufacturer data, materials analysis and verified owner feedback. It has not been through our lab. Rather than publish estimated numbers, we leave this table empty and publish no Sleep Sage performance scores 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.
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. The coil unit gives back bounce that makes repositioning effortless.
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 researched 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 were read from the brand's own site when this review was last updated and change with promotions, so confirm the price at checkout. 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
$1,799 queenChoose 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
$2,999 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.
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 catalog — and the one thing each does differently. These are research evaluations, so no numeric ratings are shown (why).
Purple RestorePlus Hybrid is a nearby alternative by price, firmness and construction. Compare the verified specifications, policies and evaluation method before choosing.
Casper Dream Max Hybrid is a nearby alternative by price, firmness and construction. Compare the verified specifications, policies and evaluation method before choosing.
Serta iSeries NXG 3500 Hybrid is a nearby alternative by price, firmness and construction. Compare the verified specifications, policies and evaluation method before choosing.
King Koil Xtended Life is a nearby alternative by price, firmness and construction. Compare the verified specifications, policies and evaluation method before choosing.
Beautyrest Black C-Class is a nearby alternative by price, firmness and construction. Compare the verified specifications, policies and evaluation method before choosing.
Want a different pairing? Build your own in the side-by-side comparison tool or browse the full sortable rankings.
Black Diamond Current Price
Queen pricing. List price $3,399, currently advertised at $2,599 (24% off).
Frequently Asked Questions
Common Themes in Owner Reviews
312 customer reviews on DiamondMattress's website. Owner feedback summarized from published customer reviews on DiamondMattress's website and major retailer listings. SleepSage cannot verify individual purchases, so no purchase-verified badge is shown. Common themes in owner reviews of the Black Diamond line up with the points below. We summarise recurring praise and complaints rather than republishing individual reviews, reviewer names, dates or helpful-vote counts, because those belong to the retailer and we cannot verify them here.
Praised most often
- 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
Most common complaints
- 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
Verified owner reviews written by Sleep Sage readers appear separately and are attributed to real accounts.
Quick Specs
- Type
- Hybrid
- Firmness
- Medium Soft
- Height
- 14"
- Trial
- 120 nights
- Warranty
- 20-year limited
How We Researched the Black Diamond
This is a research evaluation. We have not put the Black Diamond through our physical lab protocol, so this page describes the research methodology we actually used — verified construction, manufacturer specifications, policies, comparative analysis and published owner feedback.
Research Evaluation: This mattress has not completed our physical lab testing protocol, and we publish no Sleep Sage lab measurements for it. Our evaluation is based on verified construction, manufacturer specifications, policies, comparative analysis and available owner feedback.
Construction & Materials Review
We document the mattress's published layer construction, materials, densities and cover fabrics from manufacturer specifications and supporting documentation.
Specification & Certification Verification
We check published specifications, certifications and material claims against the manufacturer's own documentation, and flag anything we cannot confirm.
Policy & Price Verification
Trial length, return terms, warranty coverage, shipping and current pricing are recorded from the retailer and re-checked when we update the review.
Owner Feedback Synthesis
We summarise recurring themes in published owner feedback rather than republishing individual reviews, names or vote counts.
Comparative Analysis
We position the mattress against comparable models we have measured, using construction similarities — never by assigning it measurements it does not have.
What We Have Not Done
No pressure mapping, thermal logging, motion-transfer, edge-deflection or durability measurements were taken on this unit. We publish no lab scores until they are.
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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