diff --git a/pkgs/top-level/aliases.nix b/pkgs/top-level/aliases.nix
index a14e15e775e3..fc2f590d21f2 100644
--- a/pkgs/top-level/aliases.nix
+++ b/pkgs/top-level/aliases.nix
@@ -1602,6 +1602,7 @@ mapAliases {
   qtcurve = throw "'qtcurve' has been renamed to/replaced by 'libsForQt5.qtcurve'"; # Converted to throw 2024-10-17
   qtile-unwrapped = python3.pkgs.qtile; # Added 2023-05-12
   quantum-espresso-mpi = quantum-espresso; # Added 2023-11-23
+  quaternion-qt5 = throw "'quaternion-qt5' has been removed as quaternion dropped Qt5 support with v0.0.97.1"; # Added 2025-05-24
   quickbms = throw "'quickbms' has been removed due to being unmaintained for many years."; # Added 2025-05-17
   quicklispPackages = throw "Lisp packages have been redesigned. See 'lisp-modules' in the nixpkgs manual."; # Added 2024-05-07
   quicklispPackagesABCL = throw "Lisp packages have been redesigned. See 'lisp-modules' in the nixpkgs manual."; # Added 2024-05-07
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 6158dbf8cfbe..abc4674a66b3 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -1932,9 +1932,6 @@ with pkgs;
     charles5
     ;
 
-  quaternion-qt5 =
-    libsForQt5.callPackage ../applications/networking/instant-messengers/quaternion
-      { };
   quaternion-qt6 =
     qt6Packages.callPackage ../applications/networking/instant-messengers/quaternion
       { };