D/2 Gel vs D/2 Liquid: Which I Buy for Which Stone

headstone cleanning in Texas | headstone cleaning in New York

I’ll never forget my first big headstone cleaning job. A sweet old woman named Mrs. Kowalski hired me to clean her husband’s granite marker in a tiny cemetary outside Pittsburgh. I showed up with a spray bottle of D/2 liquid, a soft brush, and alot of confidence. Took me three tries. Worth it. The stone came out beautifully, but I learned something that day: the liquid ran down the vertical face like tears. I had to keep reapplying. If I’d used the gel, I could of slapped it on, waited, and rinsed. That moment changed how I buy D/2. Now I keep both on my truck, but I choose based on the stone. Let me walk you through the messy, real-world differences between D/2 gel and D/2 liquid — so you don’t have to learn the hard way.

What’s Actually in the Bottle? (Same Magic, Different Texture)

Both D/2 gel and D/2 liquid are the same pH-neutral, non-ionic biological cleaner. Same active ingredients. Same safe formula. No bleach, no acids, no harsh chemicals. The only difference? Thickener. The gel has a thickening agent that makes it cling to vertical surfaces. The liquid is thin — like water with a little soap. I’ve used both on marble, granite, sandstone, even slate. Never had a reaction. But here’s the kicker: the gel costs more per ounce. About $25 for a 32-ounce bottle of gel versus $20 for a 32-ounce liquid. That adds up if you’re doing a whole cemetery. So price matters. But so does time. And frustration.

When I Reach for the Liquid (Flat Stones, Large Areas, and Patience)

I buy D/2 liquid for horizontal surfaces. Flat headstones, ledger stones on the ground, or any marker that doesn’t tilt. The liquid spreads fast and covers a lot of ground — I can do a 3-foot by 2-foot flat granite slab with maybe 6 ounces. Just spray, scrub gently with a soft nylon brush, wait 10 minutes, and rinse. Also great for cleaning multiple stones in a row. I fill a garden sprayer with diluted D/2 liquid (half water, half D/2) and walk through a row of flat markers. Saves time. Big mistake using liquid on a steep vertical face though. It drips everywhere. You get runoff on the grass, which is fine because D/2 is biodegradable, but you waste product. And you have to keep spraying. For standing tombstones, the liquid just doesn’t stick long enough to break down the biological growth. So I save the liquid for the easy stuff.

When the Gel Saves the Day (Vertical Stones, Carved Details, and Stubborn Growth)

The gel is my go-to for upright headstones. Especially old marble ones with deep carved lettering. I smear it on with a cheap paintbrush — the kind you buy at a hardware store for a dollar. It stays put. Even on a windy day. I once cleaned a 150-year-old sandstone obelisk that was covered in black lichen. The liquid just ran off. I switched to gel, slathered it on thick, waited 20 minutes, and scrubbed with a soft brush. The lichen came off like butter. Never again will I use liquid on a vertical surface with heavy growth. The gel also works great for intricate carvings — angels, scrolls, flowers. The thick gel fills the crevices and doesn’t drip into the dirt. One tip: don’t let the gel dry completely. If it sits for more than 30 minutes in direct sun, it can leave a residue. Rinse it off before it cakes. Learned that the hard way on a hot July afternoon.

My Rule of Thumb for Buying (And Why I Keep Both)

Here’s my system. If I’m cleaning a flat, horizontal stone that’s just dirty with algae or moss, I buy the liquid. Cheaper, faster, less mess. If I’m working on an upright marker, especially one with carved details or heavy lichen, I buy the gel. The extra cost is worth the time saved. For mixed jobs — say a family plot with both flat and upright stones — I buy a bottle of each. The gel lasts me about 10-12 upright stones per 32-ounce bottle. The liquid goes further, maybe 20-25 flat stones per bottle. But if you’re just a hobbyist cleaning one or two family graves, get the gel. It’s more forgiving. You can always thin it with a little water if you need it runnier. Can’t thicken the liquid though. So my honest advice? Start with the gel. Then try the liquid on a flat stone and see what you prefer. Both work. Both are safe. But one will make your life a lot easier depending on the job.

Frequently Asked Questions

Q: Can I mix D/2 gel and D/2 liquid together?

A: Technically yes, but I don’t recommend it. Mixing them just gives you a weird, lumpy mess that doesn’t spray well. Better to use one or the other for a given stone. If you want a thinner gel, just add a splash of water to the gel in a cup. That works fine.

Q: Does D/2 gel work on granite or just marble?

A: Both work on any stone type — granite, marble, limestone, sandstone, slate, even concrete. I’ve used the gel on polished black granite and it didn’t etch or dull the surface. Just rinse thoroughly. The gel leaves a slight film if you don’t rinse well, so hit it with a hose or sprayer.

Q: How long should I leave D/2 gel on before scrubbing?

A: I usually wait 10-15 minutes for light moss or dirt, and up to 30 minutes for heavy lichen or black growth. Don’t let it dry out completely. If it’s hot and sunny, check it at 10 minutes. You’ll see the growth start to loosen — that’s your cue to scrub gently with a soft brush.

Q: Is the gel more expensive per use?

A: Yes, but not by much. A 32-ounce bottle of gel costs about $25, while the liquid is $20. But because the gel stays on the stone and doesn’t drip off, you actually use less product per stone on vertical surfaces. For flat stones, the liquid is cheaper per use. So it evens out depending on what you’re cleaning.

Q: Can I use D/2 gel on a dirty, unsealed limestone headstone?

A: Yes, and I’ve done it many times. D/2 is pH-neutral, so it won’t damage limestone like acids would. But limestone is soft, so use a very soft brush (natural bristle or nylon) and gentle pressure. The gel is great because it clings to the porous surface and lifts dirt without aggressive scrubbing. Rinse with low-pressure water.