Hard palate contains:
Ref. Gray’s anatomy.  41st edition. Page. 510
Hard Palate

The hard palate is located on the roof of the oral cavity, posterior and medial to the alveolar process of the maxilla.
The bony structure is formed by the palatine processes of the maxilla and the horizontal plates of the palatine bones.
The periosteum is covered by a firmly attached mucosa centrally, although a submucosa is apparent laterally containing vessels. The hard palate is continuous with the soft palate posteriorly.

Macroscopic Features
The hard palate is typically a pale pink colour and may have an orange peel appearance from the palatine salivary glands (more common posteriorly).
Microscopy
The hard palate is lined with a keratinising stratified squamous epithelium, tightly bound to the underlying periosteum of the palatine bone/maxilla. There is minimal submucosa, which becomes more prominent posteriorl
Keratinized, submucosa, minor salivary gland
Keratinized, absent submucosal layer, minor salivary gland
Nonkeratinized, submucosal layer, minor salivary gland
Nonkeratinized, absent submucosa, minor salivary gland