Question: What is is a concave golden disc of a weight of 25.23 g and a diameter of 4.5 cm, that had a king of Denmark and Norway was mentioned in the inscription of the disc?

Context articles: Aganosma cymosa
Pernik sword
Pluteus nevadensis
Lepiota babruzalka
Chisocheton ceramicus
Curmsun Disc
Harald Bluetooth
Buyla inscription
Mycena inclinata
Chionanthus macrocarpus

Aganosma cymosa is a liana that can grow up to 10 metres in length, pale brownish tomentose.
 Leaf-stalks are 1-2 cm, leaf blade broadly ovate or orbicular, 5-16 x 4-12 cm, base rounded or obtuse, apex acuminate or obtuse, rarely retuse, lateral veins 8-10 pairs.
 Flowers are borne in many-flowered clusters at branch ends, which are carried on stalks up to 6 cm.
 Bracts and bracteoles are very narrowly elliptic, 0.9-1.1 cm.
 Flower-stalks are about 5 mm.
 Calyx with several glands inside margin of sepals; sepals very narrowly elliptic, 0.9-1.1 cm, pubescent on both surfaces.
 Flowers are white, minutely tomentose outside, glabrous at throat; tube shorter than sepals, 6-7 mm; lobes oblong, as long as tube.
 Disc longer than ovary.
 Ovary pubescent at apex.
 Follicles 2, cylindric, to 30 X 0.8-1.2 cm, yellow hirsute.
 Seeds oblong, 1-2 cm X ca. 5 mm, coma 2-4.5 cm.It is native to China (Guangxi, Yunnan), Bangladesh, India, Sri Lanka, and Indochina (Cambodia, Laos, Thailand, Vietnam).
The Pernik sword is a medieval double-edged iron sword unearthed in the ruins of the medieval fortress of Krakra near Pernik, western Bulgaria, on 1 January 1921.
 It bears an inscription in silver inlay on the blade.
 The sword is preserved in the National Archaeological Museum of Bulgaria in Sofia.
 The sword is 96 cm long and up to 4.5 cm wide.
Pluteus nevadensis is a species of fungus in the agaric family Pluteaceae.
 Described as new to science in 2010, the species is known only from subtropical and pine forests in Mexico, where it grows on rotting pine and oak wood.
 Fruit bodies (mushrooms) have red-orange caps up to 3.8 cm in diameter with a shape ranging from conic, convex, or flattened, depending on their age.
 The silky yellow stems are up to 4.5 cm long.
 It is similar in appearance to "Pluteus aurantiorugosus", with which it shares an orange- or scarlet-colored cap and a yellow stem.
 "P. nevadensis" can be distinguished from this and other superficially similar "Pluteus" species by differences in microscopic characteristics.
Lepiota babruzalka is an agaric mushroom of the genus "Lepiota" in the order Agaricales.
 Described as new to science in 2009, it is found in Kerala State, India, where it grows on the ground in litterfall around bamboo stems.
 Fruit bodies have caps that measure up to 1.3 cm in diameter, and are covered with reddish-brown scales.
 The cap is supported by a long and slender stem up to 4.5 cm long and 1.5 mm thick.
 One of the distinguishing microscopic features of the species is the variably shaped cystidia found on the edges of the gills.
Chisocheton ceramicus is a tree in the Meliaceae family.
 It grows up to 30 m tall with a trunk diameter of up to 40 cm .
 The bark is dark brown.
 The fragrant flowers are pinkish.
 The fruits are roundish, orange-red, up to 4.5 cm in diameter.
 The tree is named for Seram Island in Indonesia's Maluku.
 Habitat is forests from sea-level to 1100 m altitude.
 "C. ceramicus" is found in Thailand, Vietnam, throughout Malesia and New Britain.
Curmsun Disc is a concave golden disc of a weight of 25.23 g and a diameter of 4.5 cm .
 The Danish Viking king, Harald Bluetooth, is mentioned in the inscription of the disc.
Harald "Bluetooth" Gormsson (Old Norse: "Haraldr Gormsson" , Danish: "Harald Blåtand Gormsen" , died c. 985/86) was a king of Denmark and Norway.
The Buyla inscription is a 9-word, 56-character inscription written in the Greek alphabet but in a non-Greek language.
 It is found on a golden buckled bowl or cup which is among the pieces of the Treasure of Nagyszentmiklós which are now in the Kunsthistorisches Museum in Vienna.
 The bowl is 12 cm in diameter and weighs 212 g, and has a handle or buckle, perhaps for hanging on a belt.
 The inscription is found around the outside of a circular design in the middle of the bowl.
 In the place where the inscription begins and ends, there is a cross.
 The inscription reads: ΒΟΥΗΛΑ·​ΖΟΑΠΑΝ·​ΤΕϹΗ·​ΔΥΓΕΤΟΙΓΗ·​ΒΟΥΤΑΟΥΛ·​ΖΩΑΠΑΝ·​ΤΑΓΡΟΓΗ·​ΗΤΖΙΓΗ·​ΤΑΙϹΗ .
Mycena inclinata, commonly known as the clustered bonnet or the oak-stump bonnet cap, is a species of mushroom in the family Mycenaceae.
 The doubtfully edible mushroom has a reddish-brown bell-shaped cap up to 4.5 cm in diameter.
 The thin stem is up to 9 cm tall, whitish to yellow-brown at the top but progressively becoming reddish-brown towards the base in maturity, where they are covered by a yellowish mycelium that can be up to a third of the length of the stem.
 The gills are pale brown to pinkish, and the spore print is white.
 It is a widespread saprobic fungus, and has been found in Europe, North Africa, Asia, Australasia, and North America, where it grows in small groups or tufts on fallen logs and stumps, especially of oak.
 British mycologist E.J.H. Corner has described two varieties of the mushroom from Borneo.
 Lookalike species with which "M. inclinata" may be confused include "M. galericulata" and "M. maculata".
Chionanthus macrocarpus grows as a tree up to 30 m tall, with a trunk diameter of up to 60 cm .
 The flowers are white.
 Fruit is bluish green when fresh, ellipsoid, up to 4.5 cm long.
 The specific epithet "macrocarpus" is from the Greek meaning "large fruit".
 Habitat is mixed dipterocarp forest from sea-level to 1700 m altitude.
 "C. macrocarpus" is found in Sumatra, Peninsular Malaysia, Borneo and Java.