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In this guide
Diamonds - sparkly in your jewellery, but not commonly found in your bed. Until now that is.
Emma offers 2 mattresses, the Emma Comfort and the Emma Diamond Hybrid mattress. The Emma Diamond is the more premium offering, boasting foam and springs, compared to the Emma Comfort’s all-foam design. Promising a cool and comfortable night’s sleep, does it deliver? Find out in our Emma Diamond mattress review. We’ll take you through everything from its materials to what it feels like to sleep on and its suitability for hot sleepers. We’ve also got first-hand experience as Cosier writer Ali sleep tested it.
At a glance
- The pressure relieving feel of the mattress that moulds to your body.
- Great suitability for hot sleepers.
- None to very little motion transfer.
- Very little off-gassing smell.
- Even though Emma says it’s medium-soft, most sleepers find it firm especially for the first few weeks. Our sleep tester Ali reckons it’s medium to firm.
- Lack of edge support makes the sleepable area of the mattress feel smaller.
- Rope in someone to help you manoeuvre the mattress as it’s quite heavy.
Who’s the Emma Diamond Hybrid mattress best for
Hot sleepers, people who have particularly wriggly co-sleepers or people who need extra back support will find a lot to enjoy in the Emma Diamond mattress. With prices starting from $1,599 this is definitely more a master bedroom mattress than a guest or kid’s one.
Ali reckons side and back sleepers who prefer a medium to firm mattress will love the Emma Diamond. Because it combines the hugging feel of foam with the support of springs, weight is distributed evenly making it a good choice for anyone with back pain.
What you need to know
Ordering and delivery
Ordering the Emma Diamond online isn’t the easiest experience we’ve had. There’s a lot going on with pop ups and chat boxes and big ol’ promos. The Emma Comfort is more visible on the website, with the Diamond tucked away about halfway down the homepage or accessed via the top menu.
Once on the right page, it’s a case of scrolling down a lot of info (features, delivery time, size and financing options). We appreciate that Emma makes delivery timeframes clear. The latest information is in an easy to spot coloured box. When you select the size, the time frame is shown. Currently, the biggest mattresses have an 1-7 day lead time.
After it's added to your cart, a pop up appears to encourage you to go for some optional extras, like a pillow or mattress topper. Clicking out of that, you can finally get to your cart. From there, it’s plain sailing. Add your details and delivery address, then your payment details (they accept credit card, PayPal and financing), agree to the T&Cs and you’re done.
The lack of shipping information isn’t great - it simply tells you it’s free, with no further details provided about the delivery time frame. Koala does this really well by allowing you to choose a delivery date and time. Emma, not so much.
The Emma Diamond is delivered in a tall skinny box with the same dimensions as the Emma Comfort. That’s 38 x 38 x 110cm for the single, king single and double and 45 x 45 x 110cm for the queen and king. Because it’s contactless delivery, it’ll be delivered to your doorstep but won’t be taken inside your home. The king weighs 40kg so it’s fairly hefty to move by yourself - but nothing compared to the Koala Calm As king which weighs 51.75kg.
Ali lives in New Zealand where the Emma Diamond Hybrid mattress isn’t currently sold. That meant it wasn’t delivered through Emma’s regular delivery partners. So, there was a customs hold up for a few weeks. One box was partially opened and a bit worse for wear, but the contents were fine.
Materials and construction
Unlike the Emma Comfort, the Emma Diamond is a hybrid mattress. This means it’s got both foam and springs in 4 layers:
- Diamond Degree graphite foam which helps prevent heat build up and reduces partner disturbance.
- Adaptive comfort foam which is pressure relieving and responds as you move for all-night comfort.
- Pocket springs which increase air flow for a cool night’s sleep and minimise partner movements.
- HRX foam for extra support, especially for your back.
The Emma Diamond mattress has a removable and washable cover that’s 99% polyester and 1% elastane. The bottom of the cover is 100% polyester, while the base is 87% polyester and 13% polypropylene.
If you’re wondering about the safety and sustainability of the materials, Emma doesn’t really shout about it. Tucked away in the quality mark accordion you’ll find info that states that every layer complies with OEKO-TEX® Standard 10 which means it’s free of harmful substances .
What the Emma Diamond Hybrid mattress feels like
Emma states the Emma Diamond is a medium-soft mattress. It seems like plenty of Aussie sleepers disagree, with most calling out how firm it is. This doesn’t mean that they find it uncomfortable (they don’t), but most say it takes a while to get used to it. Ali found it was a medium to firm mattress and we’re confident in saying you should expect a somewhat firm feeling mattress. Some reviewers have reached out to Emma and been quickly provided a top comfort layer to soften the mattress. The Emma Comfort has the same issue, with most sleepers finding it more firm than medium.
Because of the supportive foam, you’re going to feel a gentle moulding sensation as it contours to your body. Think of it as a little hug as you move around. Pressure relieving, it should feel comfortable whatever sleeping position you’re in. Ali is a combo side and back sleeper and found it comfy in both of those sleeping positions. It won’t bounce or move much (it doesn’t have the springiness of latex), which makes it good for co-sleepers.
Oh, and Ali points out that there isn’t a lot of edge support. This means the sleepable area of the mattress feels smaller.
There’s a lot of tech in the Emma Diamond mattress that’s designed to minimise partner disturbance. This includes the top layer of foam that’s got low rolling resistance, making it smoother and easier for you to move and less disruptive to you and your sleeping partner. The pocket springs also help by isolating any movement.
Most sleepers agree that there isn’t much partner disturbance. This was Ali’s experience too. Her partner has restless legs and often tosses and turns all night, but on the Emma Diamond she didn’t get disturbed. Result.
Suitability for hot sleepers
The Emma Diamond cover is highly breathable and allows air to circulate throughout the mattress. The top layer of foam has a special coating that removes excess heat. While the individually wrapped pocket springs help with air flow and breathability too. A lot of sleepers think that the Emma Diamond is a deliciously cool mattress, making it a good choice for hot sleepers.
Ali sleep-tested it during winter and it felt cool and comfortable.
As a tightly compressed mattress, rolled in plastic, popped in a box and sent hundreds of kilometres away, mattresses in a box, especially those with foam, can release a weird, chemical smell when you unroll them.
There aren’t many customer comments about off-gassing. If you did notice something, Emma recommends putting the mattress in a well ventilated space for a few days and washing the cover.
Ali reckons there’s very minimal off-gassing smell right from the start, which completely disappeared by the second night.
Emma is a no frills brand, focusing more on the tech than anything else. It offers a lot of the same things as the rest of the mattresses in a box brands without any extras. It’s got a free trial (a standard 100 nights), a warranty (10 years, one of the shortest we’ve seen) and free shipping and returns (standard). If you’re after a mattress with more of a focus on environmentally-friendly or sustainable manufacturing, Emma probably isn’t right for you.
How much does the Emma Diamond Hybrid mattress cost?
Prices start from $1,599 for a single mattress, up to $2,499 for a king.
Trial, warranty and shipping
You’ve got 100 nights to try the Diamond. If it’s not right for you within this time, you can send it back. Emma asks that you give it at least 3-4 weeks before returning it. Returning it involves emailing them to arrange a free pick-up. This only applies to customers within their delivery area. Customers outside these areas (which aren’t listed on their website) need to take the mattress to their nearest drop off location, at their own time and expense. Once Emma has the mattress, they refund you within 14 days.
The Emma Diamond mattress has a 10-year warranty. This warranty covers sags or dips that are greater than 2.5cm, cracks or hollows in the foam, a mattress that doesn't fully inflate within 2 weeks, and damage to the cover (but not normal wear and tear). Claiming under the warranty involves emailing Emma with photos of the problem.
Emma offers free shipping, Australia-wide. Delivery timeframes vary massively. For in stock Diamond mattresses, you’re looking at 1-7 business days. But for those on backorder, it can be between 6 to 9 weeks. Unfortunately this seems to be where Emma struggles. There are some unhappy Aussies complaining that shipping has either been massively delayed (way beyond 6-7 weeks and into 4-6 months) or simply hasn’t turned up. Communications with Emma have been reduced to automated emails telling customers their order is delayed. It’s a shame that these shipping issues seem to be detracting from a great mattress.
How the Emma Diamond Hybrid mattress compares to the Emma Comfort mattress
The Emma Diamond mattress is a hybrid which contains both foam and springs, while the Emma Comfort is an all-foam mattress. The Diamond has 4 layers, compared to the Comfort’s 2. The price is different too, with the Diamond starting at $1,599 and the Comfort at $899.
Or how to get up on the right side of the bed every morning.