diff --git a/docs/learn/fundamentals/crystal-systems.yaml b/docs/learn/fundamentals/crystal-systems.yaml
index 44c5876..827bd6d 100644
--- a/docs/learn/fundamentals/crystal-systems.yaml
+++ b/docs/learn/fundamentals/crystal-systems.yaml
@@ -31,7 +31,7 @@ sections:
         description: 2-fold, 3-fold, 4-fold, 6-fold rotational symmetry
       - name: Mirror Planes
         description: Reflection symmetry planes
-      - name: Center of Symmetry
+      - name: Centre of Symmetry
         description: Inversion through a point
 
   - title: The Seven Systems
diff --git a/docs/learn/origin/brazil/tourmaline.yaml b/docs/learn/origin/brazil/tourmaline.yaml
index 622f8cd..7381831 100644
--- a/docs/learn/origin/brazil/tourmaline.yaml
+++ b/docs/learn/origin/brazil/tourmaline.yaml
@@ -89,7 +89,7 @@ sections:
     subsections:
       - title: Watermelon Tourmaline
         content: |
-          - Pink center, green rim
+          - Pink centre, green rim
           - Cut to show colour zones
           - Popular collector variety
           - Good Brazilian production
diff --git a/docs/learn/phenomena/tenebrescence.yaml b/docs/learn/phenomena/tenebrescence.yaml
index cc4bcc8..bc0b3d5 100644
--- a/docs/learn/phenomena/tenebrescence.yaml
+++ b/docs/learn/phenomena/tenebrescence.yaml
@@ -37,7 +37,7 @@ sections:
         content: |
           Hackmanite is the chromatic variety of sodalite – Na₈[Al₆Si₆O₂₄](Cl,S)₂ – in which
           some Cl⁻ is replaced by the S₂⁻ disulfide radical anion. The sodalite framework
-          provides cage-like sites (β-cages) that host the color-active sulfur species.
+          provides cage-like sites (β-cages) that host the colour-active sulfur species.
 
           Kondo & Beaton (2009) described hackmanite from Myanmar and Afghanistan, documenting
           the tenebrescent colour change: hackmanite "turns pink to purple when exposed to