What is the noraml size of a Platypus egg?

Question

doing a project and would like to know

Answer 1

Wikipedia has some great stuff, here's a paragraph about the eggs:

The female Platypus has a pair of ovaries but only the left one is functional.[29] It lays one to three (usually two) small, leathery eggs (similar to those of reptiles), that are about 11 mm (7/16 inches) in diameter and slightly rounder than bird eggs.[38] The eggs develop in utero for about 28 days with only about 10 days of external incubation (in contrast to a chicken egg which spends about 1 day in tract and 21 days externally).[29] After laying her eggs, the female curls around them. The incubation period is separated into three parts. In the first, the embryo has no functional organs and relies on the yolk sac for sustenance. The yolk is absorbed by the developing young.[39] During the second, the digits develop, and in the last, the egg tooth appears.[40]

Answer 2

Approx. 15mm when laid.

A platypus egg is around the size of a thumbnail, and the female will usually lay a clutch of between one and three eggs.

http://www.bbc.co.uk/dna/h2g2/A16957056

Platypus Reproductive biology -

At the time of ovulation, the platypus egg is about 0.16 in (4 mm) in diameter.

After being fertilized, the first of three shell layers is formed in the fallopian tube before the egg moves into the uterus.

There, the egg is supplied with additional nutrients and two more shell layers are secreted, so the egg is about 0.6 in (15 mm) in diameter when it is laid. Though the time required for gestation has never been determined precisely, it is believed that it takes around three weeks.