diff --git a/src/Cast/GeometryCast.php b/src/Cast/GeometryCast.php
index 15afa03..072428c 100644
--- a/src/Cast/GeometryCast.php
+++ b/src/Cast/GeometryCast.php
@@ -48,6 +48,10 @@ public function get($model, string $key, mixed $value, array $attributes)
         if (! isset($value)) {
             return null;
         }
+        if ($value instanceof Geometry) {
+            $this->assertGeometryType($value);
+            return $value;
+        }
 
         // Detect format: WKB data is hex-encoded, WKT is human-readable text
         // After serialization, the model contains the WKB value, and we need to