Tektites, are by definition, created by a meteorite impact. The "space rock" hits the earth, melting the ground around it, flings it up into the air where it cools and come back to earth, creating what we know as Tektites. How high and far they are spread around varies depending on the power of the impact. Examples of true Tektites include Moldavite, Darwin Glass and Indochinite.

Pseudo-tektites are on the other hand, are things that look like Tektites at first glance, but are actually usually ancient forms of obsidian, which is a volcanic glass. Both real and pseudo-tektites are both technically glass, but one is created by an extra-terrestrial event, and the other by volcanic activity here on earth.

A green Tektite created around 14 million years ago by a meteorite impact that formed the Nördlinger Ries crater in northern Germany. It threw the molten glass into air, creating a large spread across Czech Republic and some finds have also been documented close to neighbouring countries borders.

A Tektite found near the Mount Darwin Crater in Tasmania, formed in an impact from around 800,000 years ago. Unlike most Tektites which form droplets and more rounded forms, Darwin Glass is often twisted and bent.

A large spread of Tektites found across southeast Asia & Australia, named after the former French colony area known as Indochina. These are a dark brown - black and often found in larger pieces, and are around 700,000 years old.

One of the most commonly available pseudo-tektites seen on the market. Although it's often claimed to be a Tektite, this material was actually formed from volcanic activity in Indonesia, not a meteorite impact, so cannot be called a Tektite

A pseudo-tektite named after Colombia, where it is found, and also referred to as "Cali Glass", after the city of Cali in Western Colombia. It is estimated that this weathered obsidian is around 30 million years old. Little of this material is available compared to the larger deposits of Agni Manitite and Indochinite, so it tends to be more on the expensive side.

This pseudo-tektite is named after the city of Safford, Arizona, outside which these can be found. Like Colombianite, little material is collected and sold so these are much rarer to find on the market.

Different Tektites & Pseudo-tektites will have wildly varying prices, caused by various factors. Agni Manitite is found in much larger quantities than other pseudo-tektites like Saffordite & Colombianite, so will generally be much cheaper than these two. It's also much more common to find larger pieces of it.

The price of Moldavite shot up due to social media trends, so the price of it per gram is much higher than some of the pseudo-tektites like Saffordite, despite the fact that there is a lot more Moldavite dug every year than Saffordite. Tektites will also vary in price by location and desired formations, Indochinite is a great, affordable option if you're looking for a cheaper Tektite to add to your collection.

Pictures:

Top left - Moldavite

Top right - Darwin Glass

Bottom left - Agni Manitite

Bottom right - Saffordite