Accessing various elements from a raw vertex buffer

Is the following code valid? It's a sample of how I'm trying to get the position of the vertex with index 13, from the raw vertex buffer.

I'm assuming the first stream consists of 3 floats32 (positions) and 2 floats16 (uv), hence 16 bytes per vertex (only working with the 0th vertex buffer here).

Code (CSharp):

1. int bytesPerVertex = 16;
2. int bytesPerPosition = 4; // could be 2 if float16
3. int vertexIndex = 13; // index I want to get the position for
4.  
5. var vertexBuffer = meshData.GetVertexData<byte>(0);
6. byte* vertexBufferPtr = (byte*)NativeArrayUnsafeUtility.GetUnsafeReadOnlyPtr(vertexBuffer);
7.  
8. byte* ptr = vertexBufferPtr + 13 * bytesPerVertex;
9. float xPosition = ((float*)tempPointer)[0];
10. ptr += bytesPerPosition;
11. float yPosition = ((float*)tempPointer)[0];
12. ptr += bytesPerPosition;
13. float zPosition = ((float*)tempPointer)[0];

Is there a better way of doing this? Just reinterpreting the array as NativeArray<float> works in most cases, but there's no guarantee the array only consists of 4byte elements, and in that case I need a more general approach.