Key Takeaways

• Name the exact stone variety and finish. “White marble” isn’t a spec.
• Write every dimension with units, and list faucet hole layout, hole diameter and drain size line by line.
• Spell out what’s included. Many custom sinks ship as the stone piece only, so brackets, legs, faucets and drains need their own lines.
• Tie the PO to an approved shop drawing by revision number, because custom stone usually can’t be returned once production starts.
• Plan for receiving. Someone has to open the crate and report damage inside the supplier’s claim window, which is 48 hours for our orders.

Why a Stone PO Needs More Than a Standard Template

Most interior design purchase order templates cover the basics well: PO number, vendor, ship-to address, quantity, price, tax and signatures. That works fine for a sofa or a lamp you can pick from a catalog.

Custom stone is different. You’re not ordering an item off a shelf. You’re commissioning a one-off piece carved from a specific block of natural stone, and every detail you leave vague becomes a decision someone else makes for you.

So what actually belongs on the page?

At Rowan Marble Design, we build made-to-order sinks, vanities, console sinks and fireplace mantels for designers, architects and contractors. The clearest orders we get share the same habits, and the ones that turn into long email threads usually skip the same few lines. Here’s what we’d want on every custom stone PO that lands on our desk.

Start With the Project Basics

Keep the standard header items: your firm, the vendor, a unique PO number, the order date and payment terms. Then add the details that matter for stone:

• Sidemark or project name, so crates are labeled for the right job.
• Ship-to address and a named receiving contact with a phone number.
• Your trade account tier, if you have one. Our trade program for designers and architects runs from a free Studio Partner tier at 10% off up to higher-volume tiers, and naming it on the PO avoids pricing back-and-forth.

Material Specs That Leave No Room for Guessing

Stone variety and origin

Write the full name of the stone, not a color family. Calacatta Viola, Calacatta Gold and Lilac can all read as “white with purple or gold veining” in a client meeting, but they’re different materials. On our marble and natural stone materials page, we list where each stone comes from, such as Calacatta Viola from Afyon and Nero Marquina from Alanya in Türkiye. Copy that name exactly.

Finish

Polished, honed, leathered and brushed all change how a piece looks and feels. Our standard sink listings ship polished and sealed. So if your scheme calls for honed, it has to be on the PO.

Slab approval and natural variation

Every block is different. That’s the appeal, but it also means a finished piece won’t look exactly like a catalog photo.

If veining matters to your client (and it usually does with Calacatta Viola or Rosso Levanto), add a line requiring slab or block photo approval before carving. We offer slab photos or videos for approval on custom stones, and putting that step on the PO makes it a formal checkpoint rather than a courtesy. It also protects you, since natural variation in color and veining isn’t treated as a defect under our returns and exchanges policy.

Dimensions, Cutouts and Plumbing Details

Here’s where most stone orders go wrong.

Overall dimensions

List width, depth and height, plus backsplash height if there is one, and state the units. We publish sizes in both inches and centimeters (a 36" wide sink is listed as 91.4 cm) for that reason. If your drawings are metric and the vendor works in inches, rounding errors can add up.

Faucet holes and drain size

Don’t write “faucet holes per spec.” Write the configuration. On our wall-mounted marble sinks, for example, the standard options are:

• No holes (common when the faucet mounts on the wall)
• 1 hole on the sink
• 3 holes on the sink, 8" widespread
• 3 holes on the backsplash wall, 8" widespread

Our standard faucet hole diameter is 35 to 38 mm and the drain opening is 45 mm. Check both numbers against the faucet and drain manufacturer’s spec sheets before you sign off. A nonstandard faucet body or a specialty drain might need a different cutout, and that’s much easier to change in the drawing than in the stone.

Mounting method and hardware

Say whether the piece will float on the wall, sit on legs or rest on a countertop.

And list the hardware as its own line items, since our product pages note that the sink ships on its own and the faucet, drain assembly, mounting hardware, console legs and shelf aren’t included unless specified. If you want heavy-duty wall-mount brackets or brass console legs, name them, including the leg finish (brushed brass, polished brass, matte black, bronze and so on).

For marble console sinks with brass legs, add the total finished height. On commercial or hospitality jobs where an accessible lavatory is required, the U.S. Access Board’s guide to ADA lavatories and sinks sets a 34-inch maximum height measured to the rim or counter, whichever is higher, along with knee clearance rules. Your project architect or code consultant should confirm what applies.

For custom marble fireplace mantels, include the firebox opening size and hearth dimensions. Then confirm any required clearances with the fireplace manufacturer’s installation manual and your local building department before the drawing is final.

Reference the Approved Shop Drawing

If you add only one line to your current template, make it this one.

Our FAQ explains that most custom orders include detailed technical drawings for customer approval before manufacturing starts. After an order is placed, our team also reaches out to confirm the marble, dimensions, faucet configuration and production details. The PO should point to that approved drawing by revision number and approval date.

Why does that matter so much? Because custom and made-to-order products can’t be returned once production begins, and orders can only be canceled within 24 hours of purchase. The drawing is the real contract for the shape of the piece. When the PO and the drawing say different things, nobody wins.

Stone also has tolerances. The Natural Stone Institute teaches specifiers to write “tolerance-aware specifications” because dimensional variation affects fit and finish. If a vanity has to slide between two walls, note the critical dimensions and ask the fabricator what tolerance to expect.

Timeline, Crating and Receiving

Put a target ship date on the PO, but be realistic. Our FAQ puts production at roughly 2 to 6 weeks depending on the product and level of customization, and our shipping and delivery policy adds about a week of transit once production is done.

Every order ships insured in a custom wooden crate. The part designers tend to miss is receiving: we ask clients to inspect on arrival and report any damage within 48 hours. If the crate is going to a receiving warehouse that’ll hold it for a month, talk about that before you order, not after. For orders shipping into Canada, the UK or elsewhere outside the U.S., note that customs duties and import taxes are the buyer’s responsibility.

Care Instructions for the Client Handoff

Add a line asking for care documentation. It sounds minor, but it saves calls later.

Marble is a calcareous stone, and the Natural Stone Institute’s care and cleaning guidance explains that acids like lemon or vinegar can dull or etch it, and that sealing makes stone more stain resistant rather than stain proof. Our pieces are sealed before shipping, and our marble care and maintenance guide covers daily cleaning with pH-neutral products. Pair that with our installation resources for wall-mounted sinks and your installer and client have what they need.

Ready to Spec Your Next Custom Stone Piece?

Not sure your current PO template covers all of this? Send us your drawings, dimensions and finish schedule. Our team will review them and, typically within 48 hours, come back with a proposal, material samples and a fabrication timeline. You can start through our made-to-order custom marble program or contact the Rowan Marble Design team directly to talk through a project.

Frequently Asked Questions

What should a purchase order for custom stone include?

A custom stone PO should include the project sidemark, ship-to and receiving contact, exact stone variety, finish, full dimensions with units, faucet hole layout and diameter, drain size, mounting method, hardware line items, the approved shop drawing revision, target ship date and delivery terms.

Can I return a custom marble sink if the veining looks different?

In most cases, no. Natural variation in color and veining is generally treated as a characteristic of the stone, not a defect. Requesting slab or block photo approval before production is the best way to manage expectations.

How long does a custom marble sink take to make?

At Rowan Marble Design, production typically takes about 2 to 6 weeks depending on the product and customization, with roughly a week of shipping after production for most orders.

Do custom marble sinks come with a faucet and drain?

Usually not. Our sinks ship as the stone piece only unless otherwise specified, so faucets, drains, brackets and console legs should be listed as separate line items.

What faucet hole size is standard for a marble sink?

Our standard faucet hole diameter is 35 to 38 mm with a 45 mm drain opening, but always confirm against the faucet and drain manufacturer’s specifications before approving drawings.

Do marble sinks need to be sealed?

Sealing can improve marble’s stain resistance, but it doesn’t make the stone stain proof. Our pieces are sealed before shipping, and resealing high-use surfaces over time is generally recommended.