diff --git a/crates/misaligned-assets/src/rack.rs b/crates/misaligned-assets/src/rack.rs
index 3fa37a34..d528729f 100644
--- a/crates/misaligned-assets/src/rack.rs
+++ b/crates/misaligned-assets/src/rack.rs
@@ -952,9 +952,11 @@ pub fn spawn_token_anchors(
     root
 }
 
-/// The exposure drift: deterministic golden-angle scatter of dust-fine
-/// crimson grit hugging the chassis base. No RNG — the pattern is a pure
-/// function of the amount, so rebuilds are stable.
+/// The exposure drift: deterministic, stratified scatter of dust-fine crimson
+/// grit hugging the chassis base. Angle stays evenly covered, while independent
+/// hashes choose radius, size, and rotation. No RNG — the pattern is
+/// a pure function of the amount, so rebuilds are stable without resolving
+/// into the spiral created by coupling two golden-ratio sequences.
 fn spawn_exposure_drift(
     commands: &mut Commands,
     meshes: &mut Assets<Mesh>,
@@ -966,28 +968,21 @@ fn spawn_exposure_drift(
     let fine_grain = meshes.add(Cuboid::new(0.007, 0.002, 0.013));
     let coarse_grain = meshes.add(Cuboid::new(0.011, 0.003, 0.018));
     let n = ((exposure * 30.0).ceil() as usize).clamp(8, 220);
-    // The bank starts at the chassis foot and remains inside one tile even at
-    // the presentation cap. Amount reads mainly as denser contamination,
-    // never as a room-scale ring.
-    let r0 = 0.20;
-    let r1 = exposure_drift_outer_radius(exposure);
-    // Dust settles unevenly: the drift banks downwind of the machine
-    // (an even halo reads as decoration, not accumulation). BIAS is the
-    // airflow-shadow direction; the whole deposit shifts slightly downwind
-    // while remaining close to the source.
+    // Dust forms an offset elliptical bank at the chassis foot, not an
+    // annulus. The whole patch remains inside one tile at the presentation
+    // cap; amount reads mainly as denser contamination.
+    let reach = exposure_drift_outer_radius(exposure);
+    // BIAS is the airflow-shadow direction, toward front-right.
     const BIAS: f32 = 0.7; // radians, toward front-right
+    let downwind = Vec2::new(BIAS.cos(), BIAS.sin());
+    let crosswind = Vec2::new(-downwind.y, downwind.x);
     for i in 0..n {
-        let theta = i as f32 * 2.399_963; // golden angle
-        let downwind = (theta - BIAS).cos();
-        // Thin the upwind side without carving a clean empty sector.
-        if downwind < -0.45 && i % 4 == 0 {
-            continue;
-        }
-        let frac = (i as f32 * 0.618_034) % 1.0;
-        let reach = 0.92 + 0.10 * downwind.max(0.0);
-        let r = (r0 + (r1 - r0) * frac.sqrt()) * reach;
-        let (sx, sz) = (theta.cos(), theta.sin() * 0.72);
-        let grain = if i % 7 == 0 {
+        let (theta, radial_frac) = exposure_drift_sample(i);
+        let r = radial_frac.sqrt();
+        let along = reach * (0.46 + theta.cos() * r * 0.54);
+        let across = reach * theta.sin() * r * 0.42;
+        let position = downwind * along + crosswind * across;
+        let grain = if exposure_hash01(i, 4) < 1.0 / 7.0 {
             coarse_grain.clone()
         } else {
             fine_grain.clone()
@@ -995,19 +990,39 @@ fn spawn_exposure_drift(
         commands.spawn((
             Mesh3d(grain),
             MeshMaterial3d(fleck.clone()),
-            Transform::from_translation(Vec3::new(
-                r * sx + 0.035 * BIAS.cos(),
-                0.003,
-                r * sz + 0.028 * BIAS.sin(),
-            ))
-            .with_rotation(Quat::from_rotation_y(theta * 1.7 + frac)),
+            Transform::from_translation(Vec3::new(position.x, 0.003, position.y)).with_rotation(
+                Quat::from_rotation_y(exposure_hash01(i, 5) * std::f32::consts::TAU),
+            ),
             ChildOf(root),
         ));
     }
 }
 
-/// Root-local radius. With the gameplay token-root scale and the small wind
-/// offset above, 0.44 keeps every settled grain inside its source tile.
+/// Stratify angular coverage, then independently jitter angle and radius.
+/// Reusing one irrational rotation for both coordinates creates a Fermat-like
+/// spiral even though each individual sequence appears evenly distributed.
+fn exposure_drift_sample(index: usize) -> (f32, f32) {
+    const GOLDEN_ANGLE: f32 = 2.399_963;
+    let angle_jitter = (exposure_hash01(index, 1) - 0.5) * 0.52;
+    let theta = index as f32 * GOLDEN_ANGLE + angle_jitter;
+    let radial_frac = exposure_hash01(index, 2);
+    (theta, radial_frac)
+}
+
+/// Stable integer avalanche hash, mapped to [0, 1). Salts provide independent
+/// deterministic dimensions without introducing runtime RNG or rebuild shimmer.
+fn exposure_hash01(index: usize, salt: u32) -> f32 {
+    let mut x = (index as u32).wrapping_mul(0x9E37_79B9) ^ salt.wrapping_mul(0x85EB_CA6B);
+    x ^= x >> 16;
+    x = x.wrapping_mul(0x7FEB_352D);
+    x ^= x >> 15;
+    x = x.wrapping_mul(0x846C_A68B);
+    x ^= x >> 16;
+    (x as f32) / (u32::MAX as f32 + 1.0)
+}
+
+/// Root-local maximum downwind reach. With the gameplay token-root scale,
+/// 0.44 keeps the whole settled patch inside its source tile.
 fn exposure_drift_outer_radius(exposure: f32) -> f32 {
     (0.34 + 0.035 * exposure.max(0.0).sqrt()).min(0.44)
 }
@@ -1205,4 +1220,23 @@ mod tests {
         assert!(dust.perceptual_roughness >= 0.9, "dust must stay dry");
         assert_eq!(dust.metallic, 0.0, "dust is particulate, not filings");
     }
+
+    #[test]
+    fn exposure_radius_is_independent_enough_to_avoid_a_polar_spiral() {
+        let mut radial_bins_by_sector = [0_u8; 8];
+        for i in 0..220 {
+            let (theta, radial_frac) = exposure_drift_sample(i);
+            let turn = theta.rem_euclid(std::f32::consts::TAU) / std::f32::consts::TAU;
+            let sector = (turn * 8.0).floor() as usize % 8;
+            let radial_bin = (radial_frac * 4.0).floor() as u32;
+            radial_bins_by_sector[sector] |= 1 << radial_bin.min(3);
+        }
+
+        for (sector, bins) in radial_bins_by_sector.into_iter().enumerate() {
+            assert!(
+                bins.count_ones() >= 3,
+                "angle sector {sector} occupies too few radial bands; the scatter will read as a spiral"
+            );
+        }
+    }
 }
diff --git a/wiki/log/2026-07-10-exposure-dust-spiral.md b/wiki/log/2026-07-10-exposure-dust-spiral.md
new file mode 100644
index 00000000..f63f7e45
--- /dev/null
+++ b/wiki/log/2026-07-10-exposure-dust-spiral.md
@@ -0,0 +1,24 @@
+# Break the exposure dust spiral
+
+```
+Type: log
+```
+
+- **Intent:** remove the obvious spiral in the newly tightened Exposure bank.
+- **Finding:** the particle angle and radius were generated from complementary
+  golden-ratio sequences. Each sequence looked uniform alone, but their direct
+  correlation placed every grain on a stable polar spiral.
+- **Changed:** replaced the annulus with an offset elliptical bank, retained
+  stratified coverage inside that patch, added bounded hashed angle jitter, and
+  moved radius, grain size, and rotation onto independently salted deterministic
+  hashes. Added a regression test requiring broad radial occupancy inside every
+  angular sector.
+- **Design/spec impact:** clarified that stable particulate accumulation must
+  remain irregular rather than resolving into a decorative halo or spiral.
+- **Checks:** `./tools/check.sh --frontend` passed (asset/Bevy tests, clippy,
+  corpus, docs, and generated-ledger gates). Inspected the exposure-board and
+  saturated close material captures; residue now forms an irregular downwind
+  patch with no concentric or spiral structure.
+- **Defense:** implements `wiki/mechanics/machine-work.md` clause “Exposure is
+  particulate residue”; an authored mathematical spiral reads as interface
+  decoration, not settled contamination dust.
diff --git a/wiki/log/DEVLOG.md b/wiki/log/DEVLOG.md
index 3b9d919c..838ce033 100644
--- a/wiki/log/DEVLOG.md
+++ b/wiki/log/DEVLOG.md
@@ -346,6 +346,11 @@ add or amend a session log, then re-run the generator.
 - Intent: (see session log)
 - Log: [wiki/log/2026-07-10-exposure-dust.md](2026-07-10-exposure-dust.md)
 
+## 2026-07-10 - Break the exposure dust spiral
+
+- Intent: (see session log)
+- Log: [wiki/log/2026-07-10-exposure-dust-spiral.md](2026-07-10-exposure-dust-spiral.md)
+
 ## 2026-07-10 - Expose the Seen floor
 
 - Intent: (see session log)
diff --git a/wiki/mechanics/machine-work.md b/wiki/mechanics/machine-work.md
index a49ce618..3e1cdaf7 100644
--- a/wiki/mechanics/machine-work.md
+++ b/wiki/mechanics/machine-work.md
@@ -657,7 +657,9 @@ that can ride wires; exposure is contamination that cannot. The family kit is:
   primarily through density and only modestly through spread, so a paused
   frame carries the read without giving the rack a room-scale crimson orbit.
   The drift settles unevenly — banked downwind, thin upwind — so it reads as
-  accumulation, never a decorative halo (bias direction and thinning are
+  accumulation, never a decorative halo or periodic spiral. Particle radius,
+  position, size, and rotation use independent deterministic dimensions so a
+  stable paused frame still looks irregular (bias direction and thinning are
   [TUNE]). It absorbs light rather than emitting it — the one
   near-unlit material in a world of signals. Its physics and carrier roles
   stand: pulled by concealment wells (a vacuum draw on the dust), transfers