At this point on the coast, just south of Moruya, there seem to be more beaches than there are beach names. On Saturday we explored the rock platform below the Gray Rocks car park, and headed north, along what looked like a separate beach, to a castellated honeycombed area that seemed to be a natural beach divider. Beyond that was another sheltered beach where a family group were playing with a ball and dancing around in the water. However, my beach bible lumped all these individual beaches under the same name: Bingie Beach North.

On the south side of Grey Rocks, black volcanic outcrops glistened in sun and water. Across the beach nestling under a jaunty cap of bush, the boulders were very different: smooth mottled greys, browns and terracotta. We had no names for the rocks, but plenty of speculations.

Since I had on my rock hopping shoes (new and black and blue), I hopped out onto the rocks, keeping myself steady as I tried to photograph a wave breaking in its burst of spray. I didn’t dare leap over incoming water onto wet rocks, but it didn’t matter because I could walk up a wooden staircase, passing luxuriant pigface smiling at the weather as much as I was, and reach the same point from the other side. There I could debate with J whether the thick black streak humping through the rocks was a dike, and what process shaped it like that.

On the north side of the Grey Rocks headland, the rocks were decorated with a waxy patterning of marble-like quartz, and weed glowed with a copper light. Down its belly, one rock had a strange pattern like stitches after an operation.

The castellations at the other end of this beach were sharp and full of weathered niches. However they were interspersed with clumps of smooth rounded rocks. At one point on the rock platform this junction was very clear. The strangest formations were small caves with a peaked entrance and broken-stone lintels.

Then suddenly as we walked along the sand towards Cathedral Rocks, we were hauled into the present from 450 million years ago. The people on the beach were in fact friends, three of them Poles living in Canberra. So we stood in the sun discussing bilingual children, life in a country not your birth country, good places to visit in Poland and the Polish summer dry which allowed you to wade across the Wisła up to your shoulders. It was, somehow, a disconcerting encounter, meshing as it did two of our worlds.

Volcanic rock?

Spot the junction of two distinctive kinds of rock

– caves with broken-stone lintels