Diamanthaus

Diamanthaus is not a ring shop. It is a Bern-based online seller that has spent since 2005 selling one thing: loose, certified diamonds, unmounted, sold as stones rather than jewellery. The company operates as Diamanthaus, a registered brand of Asatic AG (UID CHE-112.520.784), an owner-run Swiss stock corporation, and its own about page calls itself a pioneer in selling diamonds over the internet in the German-speaking market. For a Zurich buyer weighing up an engagement ring, that framing matters before anything else: you are not choosing a finished piece here, you are choosing the stone, and a goldsmith somewhere else turns it into the ring.

That trade-off is the whole point of the site, and it is worth being direct about it rather than letting a shopper find out mid-checkout. Diamanthaus says as much itself: buy the diamond loose, then design the piece with your own goldsmith, and treat the stone as the gift and the setting process as its own occasion. If you already have a jeweller you trust in Zurich, or you want to choose a setting independently of where the stone came from, this separation is a feature. If you want to walk out with a boxed ring in one transaction, it is not what this site does, and nothing on it pretends otherwise.

What is actually for sale

The catalogue is organised by cut rather than by finished style, which makes sense once you know everything here ships loose. The shape filters on the site cover the standard range: round brilliant, princess, emerald, asscher, marquise, heart, oval, radiant, pear (drop) and cushion. Behind each cut sits a large working inventory, which the company describes only as tens of thousands of selected diamonds rather than a fixed count, so treat that as a real but unspecific number rather than a catalogue size you can verify to the stone.

Certification matters more here than it would on a ring site, because the stone is the entire product. Diamanthaus states that every diamond over 0.3 carats carries a GIA certificate, GIA being the grading lab most buyers and most independent jewellers already trust, so a Zurich goldsmith setting a Diamanthaus stone later is working from a report they can read rather than a house grading of unknown rigour. The site backs this with its own explainer pages on the 4Cs, on certification, on pricing and on origin and ethics, aimed at a buyer who has never bought a diamond outside a finished ring before and needs the vocabulary before choosing a stone.

How a purchase actually runs

Diamanthaus advertises consultation by phone, by email or in person, and quotes prices on the site in Swiss francs, euros or US dollars depending on which currency you select, alongside a Switzerland, Germany or Austria region toggle. That currency spread is aimed squarely at buyers who think in more than one currency, which describes a lot of Zurich's international residents, though it is worth noting plainly that nothing on the site or in its terms mentions an English-language version: the shop, its knowledge pages and its terms and conditions are all in German. An expat comfortable navigating a German-language checkout will have no trouble; someone who wants the whole process in English will need to ask by phone or email whether that is possible, because the published site does not offer it.

On timing, the terms and conditions are specific rather than vague: a certified loose diamond ships within 14 working days of payment clearing, and a non-certified loose diamond within 5 working days. There is no separate published lead time for a custom setting, because Diamanthaus does not do the setting itself. Delivery is stated as insured, and the terms limit the delivery area to Switzerland, Germany and Austria specifically, so a buyer planning to leave Switzerland for a country outside that group should ask before ordering rather than assume the parcel will follow them.

Returns, warranty and the fine print

The terms give buyers a 14-day right of withdrawal on online-shop orders, with no reason required, which matches the standard Swiss and EU-influenced return window rather than anything more generous. Two things are worth flagging plainly rather than glossing over. First, that right does not apply to one-off pieces sourced to special order, or to anything not listed in the online shop itself, so a bespoke stone tracked down specifically for a customer is final sale. Second, a return is not free: Diamanthaus charges a processing fee of 30 CHF for a return sent from within Switzerland, and 100 EUR for a return sent from any other country, deducted from the refund. Neither figure is hidden; both sit in the same terms document as the return right itself. A general warranty of 1 year applies to purchases unless something different is agreed in writing, and it lapses if the stone is mishandled or altered by a third party after delivery, which in practice means once a Zurich goldsmith sets it, keep any paperwork from that work too.

Payment runs by advance bank transfer or Twint online, with card and Twint options available for in-person transactions; the terms specify that any order from 15,000 CHF upward is accepted only against advance payment, not on any deferred basis. That threshold is worth knowing before you start configuring a stone near that value, since it rules out paying on delivery for a serious purchase.

The customs-free storage option, and where it actually applies

The brief for this listing flagged a customs-free storage option, and it is real, but it sits specifically inside Diamanthaus's investment-diamond service rather than attaching to every ring-bound stone a Zurich buyer might purchase. The company's Zollfreilager (bonded warehouse) page describes a securely guarded storage facility where diamonds can be held for an unlimited period without Swiss VAT or customs duty accruing, with tax only becoming due if and when the stone physically enters a country. A sale straight out of the facility to a foreign buyer stays untaxed. The numbers behind it are specific: an annual fee of roughly 0.42% of the stone's value plus a base charge (the site gives an example of 1,200 CHF a year), on top of a 500 CHF handling charge per Zollfreilager transaction from Diamanthaus itself. The site is candid that the base fee only makes this worthwhile from six-figure values upward, and it frames the tax saved by storing rather than importing at 8.1% in Switzerland, against 19% in Germany and 20% in Austria. None of that is a feature of buying an engagement-ring stone at ordinary prices; it is a parallel service for buyers treating diamonds as a store of value, and Diamanthaus keeps the two purposes on separate parts of its site rather than blending them.

Who this suits in Zurich

This is a good match for a buyer who already knows they want to choose a stone and a setting independently, has (or is willing to find) a goldsmith to do the setting, and is comfortable with a German-language process, whether that is their own German or a willingness to work through it with a translator or a German-speaking friend. It suits someone who wants a stone with a globally recognised GIA report in hand before they ever talk to a jeweller, and it suits someone who wants a Swiss-registered seller rather than an overseas marketplace, given the company's Swiss VAT registration and its Bern postal address, published as a PO box (Postfach) rather than a walk-in shop, so this is a phone-and-courier relationship rather than a showroom visit. It suits less well a buyer who wants a single vendor to handle stone and setting together, or who needs the whole transaction conducted in English from the first email.

The verdict

Diamanthaus is a specific, well-documented operation rather than a general jewellery retailer, and it is honest about that specificity in its own terms: fixed delivery windows, a stated return fee rather than a vague policy, a real company behind the brand, and a genuinely unusual customs-free storage option for buyers who want it, clearly scoped to the investment side of the business rather than oversold as a universal perk. The German-only presentation and the loose-stone-only model are real limits for some Zurich buyers, but neither is a hidden catch: both are stated plainly on the site itself, and a buyer who wants exactly what Diamanthaus does well (a certified stone, sourced from a Swiss company, at a published price and a published lead time) gets a straightforward, well-documented route to it.