Here’s a color palette based on your query that incorporates Navy Blue, Slate Gray, Mint Green, and White, along with additional colors to complete the six-color request:

### Color Palette: Serene Coastal Vibes

1. **Navy Blue**
   - **Hex Code:** 
                            
                            #0B1E2E
                        
   - **Description:** A deep, rich blue that evokes the depth of the ocean and brings a sense of stability and calmness.

2. **Slate Gray**
   - **Hex Code:** 
                            
                            #6C7A89
                        
   - **Description:** A sophisticated gray with subtle blue undertones, providing a perfect balance to brighter colors while maintaining an elegant feel.

3. **Mint Green**
   - **Hex Code:** 
                            
                            #A2DED0
                        
   - **Description:** A soft, refreshing green that adds a touch of serenity and rejuvenation, reminiscent of coastal flora.

4. **White**
   - **Hex Code:** 
                            
                            #FFFFFF
                        
   - **Description:** A pure, clean white that symbolizes clarity and simplicity, serving as a perfect backdrop for other colors.

5. **Coral**
   - **Hex Code:** 
                            
                            #FF6F61
                        
   - **Description:** A vibrant coral that injects energy and warmth into the palette, reminiscent of coral reefs and summer sunsets.

6. **Sand Beige**
   - **Hex Code:** 
                            
                            #D8CBA8
                        
   - **Description:** A warm, neutral beige that complements the coastal theme, evoking the feel of sandy shores and natural elements.

### Palette Description:
This color palette, "Serene Coastal Vibes," captures the essence of a tranquil seaside escape. The rich Navy Blue and sophisticated Slate Gray anchor the palette, while the refreshing Mint Green and clean White evoke feelings of peace and cleanliness. The addition of Coral adds a pop of vibrancy, and Sand Beige ties everything together, reminiscent of sun-kissed beaches. This harmonious blend is perfect for projects that aim to convey serenity, elegance, and a touch of warmth.