Here is a single color palette with six navy blue shades:

1. Color Name: Midnight Blue
   Hex Code: 
          
          #191970
       
   Description: A deep and rich navy blue shade reminiscent of a starry night sky.

2. Color Name: Navy Ink
   Hex Code: 
          
          #001f3f
       
   Description: A dark and intense navy blue hue, resembling the color of ink.

3. Color Name: Royal Navy
   Hex Code: 
          
          #0066cc
       
   Description: A regal and vibrant navy blue shade, evoking the color of naval uniforms.

4. Color Name: Indigo Blue
   Hex Code: 
          
          #4b0082
       
   Description: A slightly purplish navy blue tone, reminiscent of the deep indigo dye.

5. Color Name: Navy Steel
   Hex Code: 
          
          #2b3856
       
   Description: A cool and metallic navy blue shade, resembling the color of polished steel.

6. Color Name: Oceanic Blue
   Hex Code: 
          
          #0077be
       
   Description: A refreshing and bright navy blue hue, inspired by the deep blue color of the ocean.

This navy blue color palette offers a range of shades, from deep and mysterious to vibrant and refreshing, providing options for various design projects or preferences.