Position marker

Inlay on guitars or similar fretted instruments are decorative materials set into the wooden surface of the instrument using standard inlay techniques. Although inlay can be done on any part of a guitar, it is most commonly found on the fretboard, —typically the manufacturer's logo— and around the sound hole of acoustic guitars. Only the positional markers on the fretboard or side of neck and the rosette around the sound hole serve any function other than decoration (the rosette serves as reinforcement). Nacre ("mother of pearl"), plastic and wood are the materials most often used as inlay.

Some very limited edition high-end or custom-made guitars have artistic inlay designs that span the entire front (or even the back) of the guitar. These designs use a variety of different materials and are created using techniques borrowed from furniture making. While these designs are often just very elaborate decorations, they are sometimes works of art that even depict a particular theme or a scene. Although these guitars are often constructed from the most exclusive materials, they are generally considered to be collector's items and not intended to be played. Large guitar manufacturers often issue these guitars to celebrate a significant historical milestone.

Some popular fretboard inlays include rhombuses, parallelograms, isosceles trapezoids, shark fins and rectangles. Circular markers are the easiest and least expensive to produce, because drilling circular indentations and cutting circular inlays (from sheets or rods) require the least time and resources. They are typically of a color contrasting with the color of the fretboard: For example, whereas a luthier might use black for a light-colored fretboard such as maple, that same luthier would likely use white, silver, or mother-of-pearl for a fretboard made of a darker wood such as rosewood or ebony.

Many manufacturers use a distinct shape for their fret markers to create a brand identity set themselves apart from competitors. Gibson uses isosceles trapezoids while Fender uses dots, but others include lightning bolts, letters and numbers.

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