Wound contact

Hemostats

Hemostats are agents or devices used to stop bleeding (hemostasis): they help a wound form a stable clot, or they mechanically close a vessel, so that blood stays in the vascular space. In surgery the word also names the clamp that seizes a bleeder. On this page it means mineral hemostats — clays and related powders, pastes, and dressings that promote clotting by surface chemistry and absorbency, not by a metal jaw.

What illite is

Illite is a non-expandable 2:1 layered aluminosilicate of the mica group: an alumina octahedral sheet between two silica tetrahedral sheets, layers locked by potassium. Substitutions (Fe, Mg for Al; Al for Si) give a net negative surface charge in water. Cation-exchange capacity is modest (about 8–20 meq/100 g) compared with expandable smectites such as montmorillonite. It absorbs water and plasma (on the order of 20–25% of its mass in some descriptions) without swelling like a smectite gel.

Line’s field clays were described as illite–smectite rich, fine-grained, iron-bearing French greens. The hemostatic literature is therefore not a distant cousin of this archive. It is a second reading of the same mineral family: one sheet that can contact-activate clotting while another (smectite) can adsorb, concentrate, and, in Ferris’s and Quiquampoix’s work, assemble or trap organic polymers.

How it stops bleeding

The mechanisms are the ones clay physicians have used, without modern names, for centuries:

• Contact activation. The negative surface helps adsorb positively charged blood proteins and can trigger the intrinsic pathway, notably Factor XII (Hageman factor) — the same class of effect exploited by kaolin in QuikClot gauze.
• Concentration. Water and plasma are taken up; cells and clotting factors are left denser at the wound.
• Physical plug. Dry powder or paste plus dried blood forms a barrier that later detaches, often leaving a clean scar in the older patent descriptions.
• Ions and hydroxyls. Potassium-rich surfaces and metal substitutions can support coagulation and tissue interaction; biocompatibility in cited fibroblast assays is generally favourable when the mineral is clean of quartz and other contaminants.

Evidence, patents, and the commercial map

A 1995 patent describes illite-rich clay (≥50% illite) for external hemostasis: sprinkle powder until dry grains remain on the surface; a clay-and-dried-blood plug forms and later lifts away. Pastes and poultices are specified for surrounding tissue.

Later work treats illite as a partner, not always the solo star. Mixed-dimensional attapulgite (illite plus rod-like attapulgite) after acid leaching has shown short in-vitro clotting times (~134 s), less blood loss, and stronger platelet activation. Pure illite has been run in the same assays as attapulgite, montmorillonite, and kaolinite so that composition can be isolated. Some natural “kaolin” samples carry substantial illite (about 24 wt% in one analysed Chinese deposit) and still match zeolite or pure kaolin in clotting tests. Chinese patent literature describes activated illite nano-powder (20–30 nm) in electrospun or composite dressings aimed at first hemostasis and later scar quality.

Modern trauma products prefer kaolin. An earlier smectite device (WoundStat) was withdrawn over safety concerns in some settings. Illite therefore lives in mixed natural deposits, patents, and experimental membranes more than on the combat-gauze shelf. Forms in the literature include powder, granules, pastes, impregnated gauze, electrospun films, and polymer or chitosan composites. Internal or deep-bleeding use is research territory; residual mineral and embolization risk keep non-absorbable particles to external or tightly controlled surgical contexts. Purity matters.

Intersection with Line de Courssou

Line did not market a hemostat. She changed a wet green-clay poultice once a day on Buruli ulcers — necrotic, often heavily contaminated wounds that textbooks sent to the knife. The photographs show rapid non-surgical debridement and later a soft, functional scar. Illite hemostasis does not “explain” mycobacterial clearance. It does explain why an illite–smectite poultice is a rational dressing for raw flesh: it can help the wound stop leaking, hold a moist mineral interface, and come away as a plug rather than as a chemical burn. The same dual character already noted on this site — hostile to some microbes, gentle to host tissue — now has a third clause: friendly to the clot.

Read that way, the archive is not only a debridement series. It is a longitudinal record of wounds living under a mineral that modern surgery still uses, in cleaner and more specialised form, to make blood stay where it belongs.