Membrane

Membrane is a carbon removal company that turns CO2 into stone: dissolved in water and injected into basalt deep underground, most of it mineralises within two years.

From $2,500 · Carbon removal, Series A stage · sold onceBuy Membrane

Who Membrane is for

Nine of ten carbon removal startups say permanent. None shows the buyer where their tonnes are or how much is already stone.

Membrane is a carbon removal company. It dissolves captured CO2 in water and injects it into basalt deep underground, where it turns to stone. Its buyer is the head of climate at a tech company of 500 to 5,000 people, who has a net-zero claim to back and a board that asks whether the carbon stayed down.

The numbers behind it

  • 3%of the durable carbon removal tonnes contracted so far have been delivered. CDR.fyi, 2026
  • 78.5%of all disclosed durable removal tonnes were bought by one buyer, Microsoft, as of April 2026. CDR.fyi, 2026
  • >95%of the CO2 injected into basalt at a test site in Iceland had turned to stone in less than two years. Matter et al., Science, 2016

How the brand answers

Gas goes in, stone comes out, and the buyer can watch it happen to their own tonnes: where the batch sits, how much is already stone, and when it can be retired.

  • Membrane's tonne passport: crystal climbs the core as the share of the batch that is stone rises, then a share is retired

    Her batch, at its depth

    I can't prove to the board that the carbon actually stayed down.

    The passport follows one buyer's batch underground. The core runs from the wellhead down through the basalt, the batch sits in its band, and white crystal climbs through the black rock as the share that is stone goes up. A window beside it shows the rock at that depth: first a dark pore with gas in it, then pores lined with crystal.

  • The passport's delivery rows, injected, mineralising, stone and retired, under the depth column and the rock sample

    One record per batch

    Nothing ties these tonnes to a measurement I can check.

    Each batch has one record: its depth band, a sample of the rock from that band, and four dated steps, injected, mineralising, stone and retired. The step it is on now is the only thing on the screen in ultramarine.

  • The retired passport beside the stone-paper certificate with a slice of the core

    Retire it, and hold a piece

    We're paying hundreds of dollars a tonne for something nobody can see.

    Once the batch is stone, one button retires a share of it against the company's claim. The passport's headline changes to the tonnes retired, and a stone-paper certificate follows with a slice of the core set into it.

What's in the brand

Colours
  • Basalt#141517
  • Slate#3A3F46
  • Fog#C9CBCC
  • Calcite white#F2F1EC
  • Ultramarine#2B3BFF
Type
Host Grotesk for headlines and the product, Atkinson Hyperlegible Next for depths, tonnes and dates.
Name check
No company called Membrane found in carbon removal. Some membrane-tech firms use the word descriptively. A web search, not a trademark clearance.
  • Membrane key art: basalt pores lined with white crystal, one still dark with ultramarine drops of CO2
  • A black basalt ridge whose lower slopes have turned to white crystal, a small ultramarine wellhead at its foot
  • CO2 bubbles enter a fissure in black basalt as white calcite spreads across the rock
  • The Membrane logo, a three-lobed mark beside the wordmark, in basalt on calcite and calcite on basalt
  • Poster: two years in, 95% is stone
  • Poster: permanent means 1,000 years

See Membrane's homepage, live The full case on Alterra Studio

Buy Membrane

Sold once. Checkout holds Membrane for you for 30 minutes while you pay on Stripe.

  • Brand kit

    The Figma file and every asset: logo, colours, type, key art, mockups and the motion board.

    $2,500

  • Brand + homepage

    The kit, plus your homepage designed and built on it.

    $4,900

  • Brand + full site

    The kit, plus your full website designed and built on it.

    $9,500

Questions about Membrane

What do I get when I buy the Membrane brand? The Figma file and every asset: the Membrane logo and wordmark, the colour and type system, key art, product screens, mockups and the motion board. The brand is sold once, so it comes off Brandbooked when you buy it.

Can I rename Membrane or change its colours? Yes, $300 each for a new name, new colours or new type. We redo the logo and mockups to match.

Does Membrane come with a domain or trademark? No domain is included. No company called Membrane found in carbon removal. Some membrane-tech firms use the word descriptively. That is a web search, not a trademark clearance.