diff --git a/loopstructural/gui/modelling/stratigraphic_column/stratigraphic_column.py b/loopstructural/gui/modelling/stratigraphic_column/stratigraphic_column.py
index 2fc81d6..4e1607e 100644
--- a/loopstructural/gui/modelling/stratigraphic_column/stratigraphic_column.py
+++ b/loopstructural/gui/modelling/stratigraphic_column/stratigraphic_column.py
@@ -107,6 +107,7 @@ def add_unit(self, *, unit_data=None, create_new=True):
         for k in list(unit_data.keys()):
             if unit_data[k] is None:
                 unit_data.pop(k)
+        print(f"Adding unit with data: {unit_data}")
         unit_widget = StratigraphicUnitWidget(**unit_data)
         unit_widget.deleteRequested.connect(self.delete_unit)  # Connect delete signal
         unit_widget.nameChanged.connect(
@@ -116,8 +117,11 @@ def add_unit(self, *, unit_data=None, create_new=True):
         unit_widget.thicknessChanged.connect(
             lambda: self.update_element(unit_widget)
         )  # Connect thickness change signal
-
+        
         unit_widget.set_thickness(unit_data.get('thickness', 0.0))  # Set initial thickness
+        unit_widget.colourChanged.connect(
+            lambda: self.update_element(unit_widget)
+        )  # Connect colour change signal
         item = QListWidgetItem()
         item.setSizeHint(unit_widget.sizeHint())
         self.unitList.addItem(item)
diff --git a/loopstructural/gui/modelling/stratigraphic_column/stratigraphic_unit.py b/loopstructural/gui/modelling/stratigraphic_column/stratigraphic_unit.py
index 7585b96..c3125bd 100644
--- a/loopstructural/gui/modelling/stratigraphic_column/stratigraphic_unit.py
+++ b/loopstructural/gui/modelling/stratigraphic_column/stratigraphic_unit.py
@@ -1,6 +1,7 @@
 import os
 from typing import Optional
 
+import numpy as np
 from PyQt5 import uic
 from PyQt5.QtCore import pyqtSignal
 from PyQt5.QtWidgets import QWidget
@@ -24,12 +25,29 @@ def __init__(
         uic.loadUi(os.path.join(os.path.dirname(__file__), "stratigraphic_unit.ui"), self)
         self.uuid = uuid
         self._name = name if name is not None else ""
-        self.colour = colour if colour is not None else ""
+        # Convert colour from RGB tuple or string to Qt-compatible hex string
+        if colour is not None:
+            if (
+                isinstance(colour, tuple)
+                or isinstance(colour, list)
+                or isinstance(colour, np.ndarray)
+            ) and len(colour) == 3:
+                # Convert (r, g, b) to "#RRGGBB"
+                if all(isinstance(c, float) and 0.0 <= c <= 1.0 for c in colour):
+                    rgb = [int(c * 255) for c in colour]
+                else:
+                    rgb = [int(c) for c in colour]
+                self.colour = "#{:02x}{:02x}{:02x}".format(*rgb)
+            else:
+                self.colour = str(colour)
+        else:
+            self.colour = ""
         self.thickness = thickness  # Optional thickness attribute
         # Add delete button
         self.buttonDelete.clicked.connect(self.request_delete)
         self.lineEditName.editingFinished.connect(self.onNameChanged)
         self.spinBoxThickness.valueChanged.connect(self.onThicknessChanged)
+        self.setStyleSheet(f"background-color: {self.colour};" if self.colour else "")
 
     @property
     def name(self):
@@ -58,7 +76,8 @@ def onColourSelectClicked(self):
         color = QColorDialog.getColor()
         if color.isValid():
             self.colour = color.name()
-        self.buttonColor.setStyleSheet(f"background-color: {self.colour};")
+            self.setStyleSheet(f"background-color: {self.colour};")
+            self.colourChanged.emit(self.colour)
 
     def onThicknessChanged(self, thickness: float):
         """Handle changes to the thickness spinbox.
@@ -84,6 +103,10 @@ def request_delete(self):
 
         self.deleteRequested.emit(self)
 
+    def mouseDoubleClickEvent(self, event):
+        """Handle double-click event to open color selection dialog."""
+        self.onColourSelectClicked()
+
     def validateFields(self):
         """Validate the widget fields and update UI hints."""
         # Reset all styles first
@@ -111,11 +134,13 @@ def setData(self, data: Optional[dict] = None):
             self.name = str(data.get("name", ""))
             self.colour = data.get("colour", "")
             self.lineEditName.setText(self.name)
+            self.setStyleSheet(f"background-color: {self.colour};" if self.colour else "")
             # self.lineEditColour.setText(self.colour)
         else:
             self.name = ""
             self.colour = ""
             self.lineEditName.clear()
+            self.setStyleSheet("")
             # self.lineEditColour.clear()
 
         self.validateFields()
diff --git a/loopstructural/gui/visualisation/feature_list_widget.py b/loopstructural/gui/visualisation/feature_list_widget.py
index d24ca37..1159eed 100644
--- a/loopstructural/gui/visualisation/feature_list_widget.py
+++ b/loopstructural/gui/visualisation/feature_list_widget.py
@@ -144,5 +144,5 @@ def add_stratigraphic_surfaces(self):
             return
         stratigraphic_surfaces = self.model_manager.model.get_stratigraphic_surfaces()
         for surface in stratigraphic_surfaces:
-            self.viewer.add_mesh_object(surface.vtk(), name=surface.name)
+            self.viewer.add_mesh_object(surface.vtk(), name=surface.name,color=surface.colour)
         print("Adding stratigraphic surfaces...")