Overcoat Repair

This answer assumes the crack does not impact surface or inner-layer traces. CircuitWorks Overcoat Epoxy provides a rugged repairs that can actually reinforce PCB areas with more structural cracks. 

Chemtronics offers CircuitWorks Overcoat Pens in a variety of colors to match the PCB resist. Overcoat pens are basically acrylic conformal coating in convenient packaging, and the clear version can be used to coat small areas. Simply press down the pen tip and squeeze the barrel to dispense the coating material. 

Printed circuit boards (PCB) come in a variety of colors, including green, blue, red, brown, and even purple. The most common is green, but that can vary by application, industry, and the age of the PCB. Fashions change over time, and so do common PCB colors. Today, green is the most common. The reason? Not for any significant performance difference. Arguable, some colors may be easier on the eyes when assembling, soldering and reworking electronics, or work better with inspection optics. In reality, the main reason is probably price. Whatever is most common color will generally have lower cost, because bareboard suppliers are running that color continuously. Any odd color will require a change-over, extra clean-up, and thus additional cost.