After the monument was destroyed during the Reformation, relics found their way into various collections around the country.
One of them was that of Sir Walter Scott and from Saturday his Borders home will host the unique collection.
It will be accompanied by a 3D digital image of the warrior king's grave.
The computer-generated picture will form part of the exhibition, titled The Lost Tomb of Robert the Bruce, at Abbotsford, near Melrose.
It has been created using the original artefacts and the latest archaeological research by various Scottish heritage bodies.
Kirsty Archer-Thompson, heritage and engagement manger for the Abbotsford Trust said: "It is fitting that Sir Walter Scott, the man who ignited such passion for Scottish history, acquired a piece of this archaeological jigsaw puzzle.
"Everyone involved in the project is thrilled that the public can see this precious collection of remaining fragments back together again."
Following his death in 1329, Bruce was buried at Dunfermline Abbey but the grave was destroyed in 1560 when the church was ransacked by Reformers.
During the early 19th century what were believed to be Bruce's remains were discovered with fragments of carved and gilded marble from the vanished tomb.
These relics subsequently found their way into museum collections in Edinburgh, Glasgow and Dunfermline.
At least one fragment fell into the hands of Sir Walter Scott.
Historians believe he may have acquired it the same time that he acquired entrance hall panelling from Dunfermline Abbey, together with a cast of Bruce's skull.
The exhibition runs until 30 November.
It was destroyed almost 500 years ago but for the first time the remaining fragments of Robert the Bruce's ornate tomb are to be displayed together.