---
title: "Soda-lime glass — density, melting point and properties"
description: "Soda-lime glass has a density of 2,500 kg/m³ (2,440–2,530). Melting point, strength, conductivity, what it is used for, and whether it floats, rusts or is magnetic."
url: https://atoneplace.net/material/soda-lime-glass/
site: "At One Place"
---

# Soda-lime glass

**Density of soda-lime glass: 2,500 kg/m³ (2,440–2,530)**

2.50 g/cm³ · 156.1 lb/ft³

About 90% of all glass made, and the reason it is cheap is the soda: pure silica melts at 1700 °C, adding sodium carbonate drops that to around 1000 °C, and the lime is added back to stop the result dissolving in water. It has no melting point, softening gradually from about 720 °C, which is exactly what makes glassblowing and float production possible. Its theoretical tensile strength is enormous and its practical strength is 30-90 MPa, because glass always fails from a surface flaw — which is why scoring a line lets you snap a sheet along it.

## Properties

- **Density:** 2,500 kg/m³ (2,440–2,530) — 2.50 g/cm³
- **Tensile strength:** 30–90 MPa
- **Young's modulus:** 70 GPa
- **Thermal conductivity:** 1 W/(m·K)
- **Hardness:** 5.5 Mohs
- **Thermal expansion:** 9 µm/(m·K)
- **Floats in water:** No
- **Magnetic:** No

## What it is used for

- Windows and float glass
- Bottles and jars
- Drinking glasses and mirrors
- Light bulb envelopes

## How it compares

*Water is 1,000 kg/m³. Anything with a shorter bar than water floats in it.*

- air: 1.2 kg/m³
- expanded polystyrene foam: 20 kg/m³
- rigid polyurethane foam: 40 kg/m³
- Water — the float line: 1,000 kg/m³
- soda-lime glass: 2,500 kg/m³
- tungsten: 19,250 kg/m³
- gold: 19,300 kg/m³
- platinum: 21,450 kg/m³

*Water is 1,000 kg/m³. Anything below that floats.*

| Material | Density | Relative to water |
| --- | --- | --- |
| rigid polyurethane foam | 40 kg/m³ | 0.04× |
| expanded polystyrene foam | 20 kg/m³ | 0.02× |
| air | 1.2 kg/m³ | 0.00× |
| soda-lime glass ← | 2,500 kg/m³ | 2.50× |
| platinum | 21,450 kg/m³ | 21.45× |
| gold | 19,300 kg/m³ | 19.30× |
| tungsten | 19,250 kg/m³ | 19.25× |

## Does it rust?

Soda-lime glass contains no iron, so it cannot rust. Whether it degrades depends on the material, not on oxidation.

## Is it magnetic?

Soda-lime glass is not a metal and has no ferromagnetic response.

## Common questions

### What is the density of soda-lime glass?

2,500 kg/m³ (2,440–2,530), or 2.50 g/cm³.

### Does soda-lime glass float?

No. At 2,500 kg/m³ it is denser than water.

### Is soda-lime glass magnetic?

Soda-lime glass is not a metal and has no ferromagnetic response.

## Related pages

- [Does soda-lime glass float?](https://atoneplace.net/does-it-float/soda-lime-glass/)
- [Tempered glass](https://atoneplace.net/material/tempered-glass/)
- [Borosilicate glass](https://atoneplace.net/material/borosilicate-glass/)
- [Fused quartz](https://atoneplace.net/material/fused-quartz/)

## Sources

- Typical range compiled from manufacturer specifications — At One Place (/about/)