Editing Cremation (section)

=== Ash weight and composition ===
[[File:Human cremains.jpg|thumb|upright|Cremated ashes still in plastic bag]]
Cremated remains are mostly dry [[calcium phosphates]] with some minor minerals, such as salts of sodium and potassium. Sulfur and most carbon are driven off as oxidized gases during the process, although about 1–4% of carbon remains<ref>{{Cite web|url=https://www.zmescience.com/science/physics/cremation-science-memorial-diamonds-052634/|title = Cremation & the Science of Memorial Diamonds|date = 14 February 2020}}</ref> as carbonate.

The ash remaining represents very roughly 3.5% of the body's original mass (2.5% in children). Because the weight of dry bone fragments is so closely connected to skeletal mass, their weight varies greatly from person to person. Because many changes in body composition (such as fat and muscle loss or gain) do not affect the weight of cremated remains, the weight of the remains can be more closely predicted from the person's height and sex (which predicts skeletal weight), than it can be predicted from the person's simple weight.

Ashes of adults can be said to weigh from {{cvt|876|to|3784|g|lboz|-1}}, with women's ashes generally weighing below {{cvt|2750|g|lboz|-1}} and men's ashes generally weighing above {{cvt|1887|g|lboz|-1}}.<ref name="Warren, M; Maples, W (1997)">{{cite journal| last=Warren| first=M|author2=Maples, W| title=The anthropometry of contemporary commercial cremation| journal=Journal of Forensic Sciences| volume=42| issue=3| pages=417–423| year=1997| pmid=9144931| doi=10.1520/JFS14141J}}</ref>

Bones are not all that remain after cremation. There may be melted metal lumps from missed jewellery; casket furniture; dental fillings; and surgical implants, such as hip replacements. Breast implants do not have to be removed before cremation.<ref name="scoop">Ted Eisenberg and Joyce K. Eisenberg, ''The Scoop on Breasts: A Plastic Surgeon Busts the Myths,'' Incompra Press, 2012, {{ISBN|978-0-9857249-3-1}}</ref> Some medical devices such as pacemakers may need to be removed before cremation to avoid the risk of explosion. Large items such as titanium hip replacements (which tarnish but do not melt) or casket hinges are usually removed before processing, as they may damage the processor. (If they are missed at first, they must ultimately be removed before processing is complete, as items such as titanium joint replacements are far too durable to be ground.) Implants may be returned to the family, but are more commonly sold as ferrous/non-ferrous [[scrap metal]]. After the remains are processed, smaller bits of metal such as tooth fillings, and rings (commonly known as ''gleanings'') are sieved out and may be later interred in common, [[consecrate]]d ground in a remote area of the cemetery. They may also be sold as precious metal scrap.