[Solved ]What wrong with my pyramid mesh generation code?

Code (CSharp):

1. private void CreatePyramid()
2.     {
3.         Vector3[] vertices = {
4.             new Vector3 (0, 0, 0),
5.             new Vector3 (-1, 1, -1),
6.             new Vector3 (-1, 1, 1),
7.             new Vector3 (1, 1, 1),
8.             new Vector3 (1, 1, -1)
9.         };
10.  
11.         int[] triangles = {
12.             0, 1, 2,
13.             0, 2, 3,
14.             0, 3, 4,
15.             0, 1, 4,
16.             1, 2, 4,
17.             4, 2, 3
18.         };
19.  
20.         Mesh mesh = GetComponent<MeshFilter>().mesh;
21.         mesh.Clear();
22.         mesh.vertices = vertices;
23.         mesh.triangles = triangles;
24.        
25.         mesh.RecalculateNormals();
26.         mesh.RecalculateBounds();
27.         mesh.Optimize();
28.     }

Its visible from some view angles and from others not :/

 

Are the faces rotated the right way round? That's the first thing that springs to mind for me if the mesh is there.

 

Yes, the winding order was inccorect.