diff --git a/baby-gru/cloud/src/MoorhenWrapper.tsx b/baby-gru/cloud/src/MoorhenWrapper.tsx
index e42489a4..6219321f 100644
--- a/baby-gru/cloud/src/MoorhenWrapper.tsx
+++ b/baby-gru/cloud/src/MoorhenWrapper.tsx
@@ -39,7 +39,7 @@ type PdbInputFileType = {
 type MapInputFileType = {
   type: 'mtz';
   uniqueId?: string;
-  args: [string, string, moorhen.selectedMtzColumns];
+  args: [string, string, moorhen.selectedMtzColumns, {r: number, g: number, b: number}?];
 }
 
 type LegendInputFileType = {
@@ -221,20 +221,27 @@ export default class MoorhenWrapper {
     }
 }
 
-  async loadMtzData(uniqueId: string, inputFile: string, mapName: string, selectedColumns: moorhen.selectedMtzColumns): Promise<moorhen.Map> {
+  async loadMtzData(uniqueId: string, inputFile: string, mapName: string, selectedColumns: moorhen.selectedMtzColumns, mapColour?: {r: number, g: number, b: number}): Promise<moorhen.Map> {
     const newMap = new MoorhenMap(this.controls.commandCentre)
     newMap.litLines = this.context.defaultMapLitLines
     newMap.uniqueId = uniqueId
+    
+    if (mapColour) {
+      newMap.rgba = { r: mapColour.r, g: mapColour.g, b: mapColour.b, a: 1.0 }
+    }
+    
     return new Promise(async (resolve, reject) => {
       try {
         await newMap.loadToCootFromMtzURL(inputFile, mapName, selectedColumns)
         this.controls.changeMaps({ action: 'Add', item: newMap })
         this.controls.setActiveMap(newMap)
         return resolve(newMap)
+      
       } catch (err) {
         console.log(`Cannot fetch mtz from ${inputFile}`)
         return reject(err)
       }
+    
     })  
   }
 
diff --git a/baby-gru/src/types/moorhen.d.ts b/baby-gru/src/types/moorhen.d.ts
index 4aed9483..6482874a 100644
--- a/baby-gru/src/types/moorhen.d.ts
+++ b/baby-gru/src/types/moorhen.d.ts
@@ -258,7 +258,7 @@ export namespace moorhen {
         makeCootLive(glRef: React.RefObject<webGL.MGWebGL>): void;
         setColour(r: number, g: number, b: number, glRef: React.RefObject<webGL.MGWebGL>, redraw?: boolean): Promise<void>;
         fetchMapRmsd(): Promise<number>;
-        replaceMapWithMtzFile(glRef: React.RefObject<webGL.MGWebGL>, fileUrl: RequestInfo | URL, name: string, selectedColumns: selectedMtzColumns): Promise<void>;
+        replaceMapWithMtzFile(glRef: React.RefObject<webGL.MGWebGL>, fileUrl: RequestInfo | URL, name: string, selectedColumns: selectedMtzColumns, mapColour?: {r: number, g: number, b: number}): Promise<void>;
         associateToReflectionData (selectedColumns: selectedMtzColumns, reflectionData: Uint8Array | ArrayBuffer): Promise<WorkerResponse>;
         delete(glRef: React.RefObject<webGL.MGWebGL>): Promise<void> 
         doCootContour(glRef: React.MutableRefObject<webGL.MGWebGL>, x: number, y: number, z: number, radius: number, contourLevel: number): Promise<void>;
diff --git a/baby-gru/src/utils/MoorhenMap.ts b/baby-gru/src/utils/MoorhenMap.ts
index f11c0233..037c2511 100644
--- a/baby-gru/src/utils/MoorhenMap.ts
+++ b/baby-gru/src/utils/MoorhenMap.ts
@@ -46,7 +46,7 @@ export class MoorhenMap implements moorhen.Map {
         this.associatedReflectionFileName = null
         this.uniqueId = guid()
         this.mapRmsd = null
-        this.rgba = { r: 0.30000001192092896, g: 0.30000001192092896, b: 0.699999988079071, a: 1.0 }    
+        this.rgba = { r: 0.30000001192092896, g: 0.30000001192092896, b: 0.699999988079071, a: 1.0 }
     }
 
     async fetchMapRmsd(): Promise<number> {
@@ -79,7 +79,7 @@ export class MoorhenMap implements moorhen.Map {
         await Promise.all(promises)
     }
 
-    async replaceMapWithMtzFile(glRef: React.RefObject<webGL.MGWebGL>, fileUrl: RequestInfo | URL, name: string, selectedColumns: moorhen.selectedMtzColumns): Promise<void> {
+    async replaceMapWithMtzFile(glRef: React.RefObject<webGL.MGWebGL>, fileUrl: RequestInfo | URL, name: string, selectedColumns: moorhen.selectedMtzColumns, mapColour?: {r: number, g: number, b: number}): Promise<void> {
         let mtzData: Uint8Array
         let fetchResponse: Response