Byne’s decay on microscopic calcareous shells: case study of Alcide d’Orbigny’s foraminifera collections stored in Paris and La Rochelle, France Author Hairie, Clara Centre de Recherche sur la Conservation (CRC), UAR 3224, CNRS, MNHN, Sorbonne Université, Muséum national d’Histoire naturelle, case postale 21, 57 rue Cuvier, F- 75231 Paris cedex 05 (France) and Institut Lavoisier de Versailles (ILV), UMR 8180 (UVSQ-CNRS), Université Paris-Saclay, 45, avenue des États-Unis, 78000 Versailles (France) and Institut photonique d’analyse non destructive européen des matériaux anciens (IPANEMA), UAR 3641 (CNRS-MNHN-MC-UVSQ), Université Paris-Saclay - site du synchrotron SOLEIL, BP 48 Saint-Aubin, F- 91192 Gif-sur-Yvette, (France) Centre de recherche en paléontologie - Paris (CR 2 P), UMR 7207, CNRS, MNHN, Sorbonne Université, Département Origines et Évolution, Muséum national d’Histoire naturelle, case postale 38, 57 rue Cuvier, F- 75231 Paris cedex 05 (France) Author Forel, Marie-Béatrice Centre de recherche en paléontologie — Paris (CR 2 P), UMR 7207, CNRS, MNHN, Sorbonne Université, Département Origines et Évolution, Muséum national d’Histoire naturelle, case postale 38, 57 rue Cuvier, F- 75231 Paris cedex 05 (France) Author Bartolini, Annachiara Centre de recherche en paléontologie - Paris (CR 2 P), UMR 7207, CNRS, MNHN, Sorbonne Université, Département Origines et Évolution, Muséum national d’Histoire naturelle, case postale 38, 57 rue Cuvier, F- 75231 Paris cedex 05 (France) Author Müller, Camille Centre de Recherche sur la Conservation (CRC), UAR 3224, CNRS, MNHN, Sorbonne Université, Muséum national d’Histoire naturelle, case postale 21, 57 rue Cuvier, F- 75231 Paris cedex 05 (France) Author Steunou, Nathalie Institut Lavoisier de Versailles (ILV), UMR 8180 (UVSQ-CNRS), Université Paris-Saclay, 45, avenue des États-Unis, 78000 Versailles (France) Author Rouchon, Véronique Centre de Recherche sur la Conservation (CRC), UAR 3224, CNRS, MNHN, Sorbonne Université, Muséum national d’Histoire naturelle, case postale 21, 57 rue Cuvier, F- 75231 Paris cedex 05 (France) veronique.rouchon@mnhn.fr text Geodiversitas 2025 2025-10-09 47 16 659 685 https://sciencepress.mnhn.fr/sites/default/files/articles/pdf/geodiversitas2025v47a16.pdf journal article 10.5252/geodiversitas2025v47a16 1638-9395 17302384 urn:lsid:zoobank.org:pub:CC61025B-E168-4BC7-9017-686F442D323B

TABLE 1. — Overview of the condition report of d’Orbigny’s foraminifera collection. Byne’s decay is considered as occurring certainly when there is obvious crystalline growth. It is probably occurring when different unusual features, such as dissolution phenomena, are observed (see part:”Crystalline growth, but not only...”). Percentages are calculated in relation to the total number of specimens. Abbreviations: Nb, Number; Spec., specimen; prop., proportion; Diss., dissolution; Cracks, presence of cracks; White, presence of white crystals; Transp., presence of transparent crystals; Orange colour., occurrence of an orange colouration of the test; Snowball, covered by white efflorescence with a snowball aspect; Certain., certainly; Prob., probably.

				among				among				Byne’s
				which (nb.)		Crystalline		which (nb.)			decay (%)
	Nb. of	Global	Structural			growth or		Orange		Snow	Max.
Grade	spec.	prop. damage (%)		Diss	Cracks	colouration	White	Transp. colour.		ball	proport. Certain. Prob.
A	1396	39%	0%	0	0	4%	0	0	138	0	0%	0%	0%
B	1199	33%	14%	252	254	27%	834	49	182	0	30%	21%	9%
C	582	16%	14%	210	139	14%	381	85	106	31	16%	12%	4%
D + E	444	12%	12%	48	23	12%	259	129	29	80	12%	12%	1%
Total
Nbr.	3621	–	–	510	416	–	1474	263	455	111	–	–	–
%	–	100%	40%	14%	12%	57%	41%	7%	13%	3%	59%	45%	14%