Opal Pineapples

Opal pineapples are a rare type of opal that is found only in the White Cliffs region of New South Wales, Australia. They are named for their distinctive shape, which resembles a pineapple. Opal pineapples are formed when ikaite crystals, a type of calcium carbonate, are replaced by opal. Ikaite is an unstable mineral that only forms under very specific conditions, such as those found in the White Cliffs region.

Opal pineapples are very rare, and only a few hundred have ever been found. They are highly prized by collectors, and can fetch high prices.

The formation of opal pineapples is a complex process that takes millions of years. The first step is the formation of ikaite crystals. Ikaite crystals can only form under very specific conditions, such as low temperatures and high pressures. In the White Cliffs region, these conditions are met in the Cretaceous sediments.

Once the ikaite crystals have formed, they can be replaced by opal. Opal is a type of hydrated silica that forms when water and silica are present. The opal slowly replaces the ikaite crystals, eventually forming a solid opal pineapple.

Opal Pineapple specimen.
Photo: Grant Pearson

Opal pineapples can vary in size, but they are typically palm-sized. They can be any color, but the most common colors are blue, green, and yellow. Opal pineapples are often translucent, and they can exhibit a variety of play-of-color effects.

Opal pineapples are a unique and beautiful type of opal. They are a reminder of the complex and beautiful processes that take place in the Earth's crust.

Opal Pineapple specimen.
Photo: RedEarthOpal

Pineapple Opal Price & Value

Pineapple opals are one of the rarest gemstones in the world, and their price reflects that. Prices can range anywhere from $1,000 to $500,000, depending on the size, quality, and rarity of the specimen.

The most expensive pineapple opals are those that are large and have a vibrant display of colors. These opals are often cut into cabochons or other shapes that showcase their unique appearance.

Here are some additional facts about Opal Pineapples:

They are a type of pseudomorph, which means that they have replaced another mineral.
The original mineral that was replaced by opal was ikaite, which is an extinct mineral.
Ikaite crystals can only form in very cold water, so Opal Pineapples are found in the White Cliffs region, which is one of the coldest places in Australia.
Opal Pineapples are typically small, but they can grow up to 10 centimeters in diameter.
They are very rare, and only a few hundred have ever been found.
Opal Pineapples are highly prized by collectors, and they can sell for thousands of dollars.