Mesh Normal

So, i am working on a script what reads terrain data values and makes them into a mesh, i can do it fine with voxels, but when it comes to just pretty much printing the heightmap into a mesh, it has these weird " normal " issues, does this look right? is it actually the normals causing this? or could it be something else?

The flat parts are fine, its the slopes which seem to have normal issues.

Here is my script i am using :

 void renderExternalHeightmap()
     {
         Generator noise;
 
         RidgeNoise temperature = new RidgeNoise(83573);
 
         PinkNoise noiseMod = new PinkNoise(32562356);
 
         temperature.Lacunarity = 0.9f;
         temperature.Frequency = 0.01f;
         temperature.Offset = 1.2f; // sharpness
         temperature.OctaveCount = 8;
 
         noiseMod.Lacunarity = 0.9f;
         noiseMod.Frequency = 0.01f;
         noiseMod.Persistence = 1.2f; // sharpness
         noiseMod.OctaveCount = 8;
 
         noise = noiseMod;
 
 
         int X, Y, Z;
 
         X = BaseClass.WORLD_CHUNK_DIMENSION_X * BaseClass.WORLDCHUNK_LOADED_LIMIT_X;
         Y = BaseClass.WORLD_CHUNK_DIMENSION_Y * BaseClass.WORLDCHUNK_LOADED_LIMIT_Y;
         Z = BaseClass.WORLD_CHUNK_DIMENSION_Z * BaseClass.WORLDCHUNK_LOADED_LIMIT_Z;
 
         List<int> triangles = new List<int>();
 
         List<Vector3> vertices = new List<Vector3>();
 
         List<Vector2> uvs = new List<Vector2>();
 
         int index = 0; // index used for triangle work around
 
         for (int i = 0; i < 50; i++)
         {
             for (int j = 0; j < 1; j++)
             {
                 for (int k = 0; k < 50; k++)
                 {
 
 
                     vertices.Add(new Vector3(i - 0.5f, Mathf.FloorToInt(noise.GetValue(i - 0.5f, 0.5f, k + 0.5f) * temperature.GetValue(i - 0.5f, 0, k + 0.5f)), k + 0.5f));
                     vertices.Add(new Vector3(i + 0.5f, Mathf.FloorToInt(noise.GetValue(i + 0.5f, 0.5f, k + 0.5f) * temperature.GetValue(i + 0.5f, 0, k + 0.5f)), k + 0.5f));
                     vertices.Add(new Vector3(i + 0.5f, Mathf.FloorToInt(noise.GetValue(i + 0.5f, 0.5f, k - 0.5f) * temperature.GetValue(i + 0.5f, 0, k - 0.5f)), k - 0.5f));
                     vertices.Add(new Vector3(i - 0.5f, Mathf.FloorToInt(noise.GetValue(i - 0.5f, 0.5f, k - 0.5f) * temperature.GetValue(i - 0.5f, 0, k - 0.5f)), k - 0.5f));
 
                     triangles.Add(index + 0);
                     triangles.Add(index + 1);
                     triangles.Add(index + 2);
                     triangles.Add(index + 0);
                     triangles.Add(index + 2);
                     triangles.Add(index + 3);
 
                     index += 4;
 
                 }
             }
         }
 
         Mesh mesh = GetComponent<MeshFilter>().mesh;
 
         Vector4[] tangents = new Vector4[vertices.Count];
 
         for (int i = 0; i < vertices.Count; i++)
         {
             uvs.Add(new Vector2(vertices[i].x, vertices[i].z));
         }
 
         mesh.Clear();
 
         mesh.vertices = vertices.ToArray();
         mesh.triangles = triangles.ToArray();
         mesh.uv = uvs.ToArray();
         mesh.tangents = tangents;
 
         mesh.RecalculateNormals();
         mesh.Optimize();
 
     }